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Agent 21 #1

Agent 21

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When Zak Darke’s parents die in an unexplained mass murder he’s left alone in the world. That is until he’s sought out by a mysterious “I work for a government agency,” the man tells him. “You don’t need to know which one. Not yet. All you need  to know is that we’ve had our eye on you. There’s a possibility you could help us in certain… operational situations.”

Zak becomes Agent 21. What happened to the 20 agents before him he’ll never know. What he does know is that his life is about to change forever.

324 pages, Paperback

First published October 28, 2010

199 people are currently reading
3070 people want to read

About the author

Chris Ryan

342 books1,019 followers
Colin Armstrong (b. 1961), usually known by the pen-name Chris Ryan, is a British author, television presenter, security consultant and former Special Air Service sergeant.
After the publication of fellow patrol member Andy McNab's Bravo Two Zero in 1993, Ryan published his own account of his experiences during the Bravo Two Zero mission in 1995, entitled The One That Got Away. Since retiring from the British Army Ryan has published several fiction and non-fiction books, including Strike Back, which was subsequently adapted into a television series for Sky 1, and co-created the ITV action series Ultimate Force. He has also presented or appeared in numerous television documentaries connected to the military or law enforcement.

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5 stars
1,196 (41%)
4 stars
1,023 (35%)
3 stars
546 (18%)
2 stars
109 (3%)
1 star
27 (<1%)
Displaying 1 - 30 of 181 reviews
Profile Image for The Book Review Library.
29 reviews9 followers
July 22, 2012
There are a lot of teen spy books around at the moment, and I have to say I love this genre. So I was

pretty excited to read this book, as I had not heard of it before.

The book gripped me immediatly with a mysterious prologue - after that, to start with it reminded me of other popular spy books, Alex Rider and CHERUB (urgh, I HATE comparing books!), but after the first 'do you want to be a spy?' part it was more original. It was believeable - there weren't any unrealistic gadgets and the main character, Zak, recieved plenty of training before going on a mission, while in other books the character suddenly knows exactly what to do without any help!

It was full of action and excitement, however this did not make the book confusing at all! The action fitted well with the story and also seemed realistic.

I liked the characters. They were all sensible and they didn't miss hugely obvious things - sometimes I feel like shouting at character when they miss obvious things! xD We don't find out a lot about any of them, and I think it would've been nice to at least have found out a bit more about Zak, the main character, so we can get to know him better.

The ending was good - it wrapped up the book well, but still left it open for a sequel (which I will definately be reading!).

This was generally a great book, my only complaints being that it sometimes lacked original ideas and we don't get to know the characters that well. (For some reason I thought this book was about a secret agent who was 21 years old - I have no idea why.... :S)

View my book review blog: http://thebookreviewlibrary.blogspot....
Profile Image for Siobhan.
5,022 reviews597 followers
May 13, 2018
I have the terrible habit of walking into bookstores, finding a collection of books, and purchasing them because it’s a good deal – all without knowing much about the books included in the collection. Such is how I was introduced to the Agent 21 books. The pack seemed somewhat intriguing, the price was right, and I decided I would take a blind dive into the series.

I’ll be honest and say I held off on reading these once I found out a bit more about the books. Although I enjoy a good thriller, I’m not crazy about young adult thrillers. I jumped that stage in my reading development, and went straight into the adult thrillers. Due to this, my expectations of thrillers have always been much higher – to me, when I go back and read young adult thrillers, I feel as though there are things missing. This is not to say young adult thrillers are bad, simply that they do not tick all the boxes for me when it comes to my thriller reads. Nevertheless, I was intrigued by Agent 21 and decided I would give the books a try anyway – after all, I’d brought a collection.

If the truth is to be known, this book is more of a three-point-five-star rating rather than the three-star rating I gave it. The rounded down rating is a reflection of my reading mood as of late – I’ve been doing a lot of rounding down, as I haven’t felt completely blown away by most of my recent reads. Despite the rounded down rating, I did enjoy this one.

The story itself was enjoyable, leaving me turning the pages and curious to see how everything would play out. It was a book I could complete rather quickly, meaning I was powering through the story in a single sitting to get my answers. As fun as it was, it suffered from what I consider to be the usual downfalls of young adult thrillers. Things are too black and white, motives are never truly explained, and I found myself uncomfortable with a child of thirteen being thrown into such high-risk situations. Those points, however, are mostly personal preference – if you’re a fan of young adult thrillers, I’m positive the action-packed sequences of this novel will more than hold your attention.

Overall, this was great for a quick read. I’ll certainly be diving into the next two books, the other books in the collection I brought, as I’m curious to see what comes next.
Profile Image for Samantha (A Dream of Books).
1,267 reviews118 followers
February 24, 2011
I’m a big fan of the Alex Rider books by Anthony Horowitz and the Young Bond books by Charlie Higson, so when I saw this in the library and read the blurb, I picked it up immediately because it sounded like a book in the same vein. I’ve never read anything by Chris Ryan before but I know that he’s written mainly adult novels and has branched out into YA over recent years. I started ‘Agent 21’ last night and read it in one evening. It’s not a particularly long book but it was so thrilling that I couldn’t put it down.

The formula is pretty similar to other books in this genre, however unlike some series which do start to get a little far-fetched (fast cars and multiple gadgets), the story was realistic enough to believe that it could actually happen. Zac Darke is recruited by a shadowy government organisation after the death and suspected murder of his parents. He’s trained to become a teenage spy and then sent on a mission to infiltrate and capture a notorious drug lord in Mexico. Along the way he has to use all the skills he’s been taught and survive on his wits and guile alone to avoid detection.

I loved this book! It was fast-paced and exciting and a thrill-ride from start to finish. The storyline is pretty simple but well executed. Chris Ryan has plenty of experience in learning how to survive from his time in the SAS and therefore situations felt authentic and believable. I really liked Zac who makes a likeable hero. He’s intelligent and brave and clever and I enjoyed following his progression from normal teenager to fully-fledged spy. He has to make difficult choices and learn when everything isn't as black and white as it might first appear to be.

There are plenty of books about boy spys on the market but this one really stood out for me. It's full of action-packed adventure, thrills and spills and although obviously targeted at male readers would appeal to anyone looking for a great read.

The ending sets things up nicely for the sequel, although I’m hoping that there are going to be plenty more Agent 21 books to come!
Profile Image for Steve Fincher.
15 reviews
December 31, 2018
If you like books like Alex Rider and Jason Steed, you will like this. It keeps you on the edge of your seat. You tend to forget about his young age so it suits me as a Chris Ryan fan, and probably a good series of adventure books. The formula is pretty similar to other books in this genre, however unlike some series which do start to get a little far-fetched (fast cars and multiple gadgets), the story was realistic enough to believe that it could actually happen. Zac Darke is recruited by a shadowy government organisation after the death and suspected murder of his parents.
Profile Image for jessiah marielle.
205 reviews22 followers
November 14, 2022
pre-reread review: 3 stars

read this at least twice in secondary school & remember being obsessed with it…. this is the shit that got me into spy/mystery books.

i don’t know if it holds up though so this is a definite MUST reread for me. but here’s 3 stars anyway for contributing to my childhood <3 mwa
Profile Image for Majuchan.
411 reviews39 followers
August 17, 2013
Well Executed

I felt so satisfied, with all my frustration with Point Blank (Alex Rider, #2) by Anthony Horowitz are all fulfilled with Chris' Agent 21.

The characters are well developed, I love how Zak's history fit perfectly to the character he portrays... Well, he I find him much more matured than his age, but well, who would not come to maturity with your parents dead because of a mysterious fruit? I instantly care for him. It broke my heart when he is to leave his loving cousin behind and let her think that he is dead.

I can't see a single character misplaced in the story. Almost perfect indeed!

The depth of the plot is admirable, (compare to Alex Rider series.) and those lessons Zak took while at the island, well, it also got into me... the constellations and especially the Morse Code.

It does not only satisfy my story craving but it also taught me something useful. two thumbs up

I recommend this one for all that craves for a serious action minus the gore.
5 reviews
June 9, 2015
Agent 21 is a great action adventure book.
I chose this book because I love spy,crime,undercover book types.
This is my fav book and I recommend that you read the whole series.
The author is Chris Ryan former SAS soldier for the British army.
Chris Ryan has a great sense to make the reader visualise where the settting is in the story and uses technics such as onomatopoeia, simile, heaps of personification and more.
Chris Ryan's concept in the book to make a 13 year old boy Zak Drake a undercover spy is really creative.
As you would know Zak Drake(if you read the book) was really optimistic in being a spy but that changed over time.
Another reason I kept on reading this book is that literally you can't stop reading because there's no such end to it.After I completed Agent 21 I felt inside that i want to read more and sure in of he has written many more mind boggling books.

Being in the SAS has helped Chris write entertaining books I urge you to read this book it will blow your mind just like mine!!!
This entire review has been hidden because of spoilers.
Profile Image for Eloise Vanbrabant.
75 reviews2 followers
December 27, 2020
I always think there aren’t many books which are both written beautifully yet also have a wonderful plot, but this book proved me wrong! The description was great, and the plot was amazing too!! There’s this one part in the book where everything just fits together so perfectly...!! The ending drags on a bit much I thought, but I think for the rest it is amazing and is a real gripper!!
Profile Image for Lisa Langegger.
9 reviews
April 30, 2024
Listen, technically this would be a five star but the beginning was just so slow and boring and it only got interesting at like 50% but the last half of the book was great and would deserve five stars.
Profile Image for Mella_Angel .
291 reviews6 followers
September 4, 2016

Klappentext/Inhalt:
Ein Auftrag, der ihn das Leben kosten kann
Als der 14-jährige Zak seine Eltern unter ungeklärten Umständen verliert, weiß er noch nicht, wie sehr das sein Leben verändern wird. Ein seltsamer Mann taucht plötzlich auf und bietet dem Jungen eine neue Existenz an: Aus Zak wird AGENT 21. Er weiß nicht, was mit Nr. 1-20 passiert ist, doch am Ende seiner Mission soll er erfahren, was es mit dem Tod seiner Eltern auf sich hat. Zaks erster hochriskanter Auftrag führt ihn nach Mexico. Er soll sich mit dem Sohn des skrupellosen Drogenbosses Martinez anfreunden – um so an Informationen über eines der mächtigsten Kokainkartelle weltweit zu kommen. Alles läuft wie geplant, bis Martinez’ Häscher Calaca Verdacht schöpft ...

Meine Meinung:

Ich hatte schon länger mal wieder Lust auf eine Agentengeschichte und da kam dieses Buch wie gerufen. Ich hatte einige Erwartungen aber nicht zu hohe und ich wurde positiv überrascht.

Zak musste einen schlimmen Verlust verarbeiten. Dies ist für ihn nicht gerade einfach und er muss sich auch noch an ein neues Umfeld gewöhnen. Er hat eigentlich auf sein jetziges Leben gar keine Lust mehr aber er versucht sich so durchzuschlagen. Eines Tages spricht ihn ein Mann an und bietet ihm einen Ausweg an. Dafür muss er aber sein altes Leben komplett hinter sich lassen. Zak ist Anfangs verwirrt aber er sieht auch als Chance. Letztendlich geht er darauf ein und was er dann alles durchmachen muss, hätte er nicht mit gerechnet.

Zak ist natürlich sehr traurig über diesen Verlust und vermisst diese Personen. Daneben muss er sich an Leute gewöhnen, die ihn gar nicht mögen und das ist nicht immer einfach für ihn. In der Schule ist er ein Einzelgänger und er will einfach nur sein Ding durchziehen. Als er von dem Mann angesprochen wird, ist er anfangs etwas verwundert und verwirrt aber letztendlich will er dieses Leben so nicht mehr. Als er den Deal eingeht, ahnt er noch nicht was auf ihn zukommt. Als er so langsam eine Ahnung von allem bekommt, hat er Zweifel aber letztendlich stellt er sich den Herausforderungen. Er beweist großen Mut und versucht das Beste daraus zu machen.

Ich muss ehrlich sagen, dass ich jetzt nicht so hohe Erwartungen an das Buch hatte aber mir haben schon die ersten Seiten gut gefallen. Der Schreibstil lässt sich wunderbar lesen. Der Autor hat einen gewissen Humor aber es ist auch Ernsthaftigkeit enthalten. Dieser Mix hat mir gut gefallen. Des Weiteren haben wir mit Zak einfach einen absoluten genialen Protagonisten. Er stellt sich den Herausforderungen, wächst mit dem Auftrag und vieles mehr. Seine Entwicklung im ersten Band hat mir schon zugesagt. Dazu kommt noch, dass der Auftrag unglaublich spannend war und ich konnte das Buch kaum aus der Hand legen. Für mich ist es ein toller Auftakt und ich bin schon gespannt wie es mit Zak weitergehen wird.

Fazit:

Dieser Auftakt konnte mich positiv überraschen und total begeistern. Wir haben hier eine Agentengeschichte, in dem schlimme Verhältnisse angesprochen werden aber dennoch kann der Autor seinen Humor mit unterbringen. Außerdem hat mir Zak außerordentlich gut gefallen und ich bin schon auf sein nächstes Abenteuer gespannt.

Bewertung:

Cover: 5/5
Klappentext: 5/5
Inhalt: 4/5
Schreibstil: 4/5
Gesamtpaket: 4/5

4 von 5 Sterne
Profile Image for Rachel W.
191 reviews1 follower
February 15, 2014
the entire time i spent reading this, i couldn't help but compare it with Alex Rider, because, when you boil it down, it's pretty much the exact same thing.
think of it :

his parents are dead and he is living with uncle. he then gets singled out by a top secret british secret service thing because he fits a magical profile (which includes proficiency in any intellectual area, i.e. language, engineering ect as well as being unwanted by family and friendless.) the main idea behind this being 'they wont suspect kids of being spies' he is then blackmailed/threatened (sort of) to join them, and spends forever training to go on missions. he eventually goes on a mission to become the best friend of a drug lord's son (haven't seen that one before) and snoops around a bunch, gets caught, miraculously escapes, saves the day, stops the bad guy (who turned out to be the guy who murdered his family in the first place) and makes a life long enemy of his son.

do you see where I'm coming from? it's not that i didn't like it, it's just that these are so overdone and aren't really that original anymore. it just seemed like a cheap remix of the Alex Rider series,( or even the Cherub series.)

and of course, zak manages to completely piss me off by being flawless at abso-frickin-lutly everything! need you engine fixed? zak can do it! how about a radio transistor? no problem! languages? becomes fluent in 3 in 6 months! how about marksmanship? no problem, bull's-eye second try! and morse code? done in a day! yeah, so the kid was smart, but he can't be that freaking perfect at everything naturally. i mean come on, that's not exactly realistic. he's 13 and his only education has been grades 1-7 at a public school. he either already magically know everything he needs, or is unnaturally fast at learning (like, superpower fast). give me a break, unless he is some super evil genius mastermind like Artemis Fowl, that's not exactly likely that any of this could have happened ( and he's not Artemis Fowl or genius, so find this horribly frustrating. if in book two, it isn't revealed that he has magic do-everything-perfectly superpowers that help him learn so fast I'm going to be pissed)

so yes, i do intend to read further, (despite the low rating i gave it, which by the way, is 2.5) but only because i have hopes that it will get better and become a little less cliché. i hope the next one improves upon the first.
Profile Image for Dani.
127 reviews40 followers
July 25, 2014
Read the full review at: Polkadot's Book Blog

It didn't take them long to die. It never does. Not if you do it right.

For starters, I was really excited for the genre of the book because I was a really big fan of the Alex Rider series by Anthony Horowitz, so the books genre really appealed to me because it sounded so similar in a lot of ways. Which is why in the In the beginning I was really gripped and excited for what was to come. Agent 21 follows Zak Darke, who has just recently lost his parents, as he gets recruited and goes on his first ever mission for a secret government agency. The prologue was so amazing! Yet I felt that the book dragged a little after that, so it took me a while to get into it and to really enjoy the writing. Having said this, I did find the story highly enjoyable and I loved how it ended like everything tied up and connected in a neat little bow.

The characters in the book were strong and relate-able, so they felt more realistic and believable to me. Which helped me to like them and cheer them on from the sidelines because you just wanted them to survive. But then I felt that in some cases they were a little underdeveloped to me. However I think that was more down to the fact that it was the first book so I just wasn't used to the writing yet.

Overall, Agent 21 is a really enjoyable read that does encourage you to buy the rest of the series because you do get carried away with the characters and the missions that they go on. There were not a lot of things that I didn't like about the book, but in some cases there were times that I did feel slightly bored. Yet it was a quick and easy read that does meet all of it's requirements for a young adult spy novel. There was action, adventure, mystery as well as lovable characters that have a lot of room for growth. So while I didn't love it, I am really excited to carry on with the series and find out what the rest of the adventure is like for Zak Darke.
Profile Image for Katrina Ly.
141 reviews1 follower
March 24, 2012
i thought this book was pretty good. the ending was alright and slightly disturbing. good cliffhanger. its got me anticipating the sequel pretty badly, so overall, a good book. but i wouldn't say its the best i've ever read.

looking back, i've just got a bit of criticism i need to get off my chest. firstly, there was so much action in this book, there was hardly any time for character development or emotions. now, i don't know about you, but i love emotions. they are freaking crucial in any good book in my opinion. secondly, zak's grief was a little too emotionless and not enough distraught and sad in my opinion. thirdly, i kind of wish the way zak comes out of his tight spots were a little more creative and lastly

SPOILER ALERT

whats with the ending? god seriously like father like son huh? or maybe psychotic father to psychotic son, but what a personality change! seriously, at the start he was this nice shy little kid who red a lot and was seriously smart, and now his like, i wanna kill him! even though he was my friend! revenge!

you know? oh and one more little quick thing, aren't these sort of books supposed to have martial arts fighting in them? how come zak was never trained in martial arts? isn't that kind of, like, crucial to this whole spy thing?

SPOILER FINISHED

anyway, if you're looking for a light read, i strongly recommend this book. its pretty good. its basically about this kid called zak, who, after his parents are tragically killed, is recruited by an unknown government brach that the government doesn't know about (don't ask me how that works i have no idea) and then is turned into a sort-of spy. they don't actually call it spy in the book. i'm not really sure what they call themselves.

yeah anyway, give this book a go. its good.
Profile Image for Emilija.
1,899 reviews31 followers
April 16, 2021
I really enjoyed this book - I find the concept interesting and I found this book more engaging than similar books, like Robert Muchamore's The Recruit.

I admit that I did find the beginning third of the book a little slow, and I did find it a little boring, but once I hit around 40%, the plot really kicked in and I finished the rest of it in one sitting. While the plot seemed a little incredulous, there have been more incredulous events on TV and the writer is very good at making action seem real, though I presume that comes from his previous job.

The characters were well written and they all felt like they had a purpose in the plot. Zak himself is a good protagonist, and while he feels older than his age, it is well explained and I really felt a connection with the character. Michael makes me want to know more, the character on a whole is really mysterious and I just want to read more when hes involved. Gabs and Raf are both interesting, but not as involved as Zak. They're there, and they're given the beginnings of characterization, but as the book is really focused around Zak, they're not there for a large chunk of the book.
In regards to the villains of the book, I thought they were well written as well. While Martinez seemed a little weak and changed his mind frequently, I really like how his relationship with Cruz evolved. Cruz himself was an interesting character and as the book sets him up to be a bigger villain in a later book, I'm looking forward to reading about him again. And honestly, Calaca gave me shivers whenever he was involved.
This entire review has been hidden because of spoilers.
Profile Image for Cynthia.
97 reviews
July 3, 2011
Chris Ryans is simply a genius. I am a hugh fan of young adult romance, but Mr. Ryan here has changed my view immediately. now I'm into action packed adventure novels. I started by pickign this book up based on a friends recommendations of the spy industry and what not, and I finished it in about a few hours flat because of the well written tale. The fact that it also includes a biography of Ryan at the beginning of how he has faced it all and is here to tell the tale leads to authenticity.

Agent 21 is a well spun novel about a boy, Zak, who is orphened at a young age, and he questions his parent's death. Until then, his life changes when he signs onto a gathering of intelligence agency. He is forced to fake his own death. And changes his own name, just for the sake of survival. This book is so crisply written, in which you feel that you are really there. The characters never fail to disappoint you, and the concept is amazing.

Recommended from years 8 and up!!
1 review4 followers
May 9, 2024
I really like the way the author actually thought about the codenames he gave to the other agents in the book. A few great examples of this include the names Michael, Raphael and Gabriella. All of these names can be translated to archangel names as Zak finds out early in the book: Raphael translating to ‘the angel of healing’, Gabriella. translating to ‘the angelic messenger, bearer of truth and justice’, and Michael translating to ‘the great archangel.’ The author does this to show the different roles of the characters for example Raphael, the agent with the most medical experience, Gabriella, pretty much the messenger of the agents, and finally Michael, the leader of the agents. This also links to real life as names can tell you a lot about a person such as if they were to have a biblical name (such as Adam, Eve, etc.) that shows that they may be christian. However if they had a name such as Summer, April, Etc. it could tell you what time of the year they were born.
2 reviews2 followers
November 7, 2019
I really liked this book as it had a mixture of adventure and action in it. It was interesting to see what Chris Ryan had accomplished during his time serving for the army. I liked how all these stories are true and they all were told so well I could imagine being in that situation. This book has lead me to read other spy and military books and has got me fascinated with all the adventures people tell. I definitely recommend this book to adventurous people who would like a long book telling real life scenarios people get into.
Profile Image for Leensey.
312 reviews27 followers
December 5, 2025
12/5/2025:
I LOVE SPY STORIES! Zak is as compelling a character as he was when I first read this series in high school. And the budding rivalry between him and Cruz that was built on potential friendship is already breaking my heart. Love being reunited with the Guardian Angels, Raf and Gabs. All in all a solid start to this action-packed adventure!
Profile Image for Kadi P.
878 reviews140 followers
May 31, 2020
There are hundreds of teen spy books and they are all similar in some ways. However, the way this book began meant I automatically felt a connection to Zak and how hard his life has become.
This being the first Chris Ryan book I read I have to say it was FAB! I'm a big fan of CHERUB and wanted to find a book that was similar but also different and I have definitely found it!
Profile Image for Grace.
507 reviews11 followers
June 20, 2020
I bought this book by accident. I love books by Chris Ryan but realised that this one was written with young adults in mind. It was alright but not really my thing. Obviously the writing style was very different.
Profile Image for Carmi Philander.
47 reviews
January 14, 2023
Time passes quickly when you're waiting to die.
***
I honestly wished I had picked this book up sooner. The pacing, the plot, the planning—everything was pure perfection!
***
"Names, Zak, are like clothes. Easily changed. And just because a person has more than one, it doesn't mean that any of them are any less real..."
***
Despite his young age, our MC—Zak Darke—is witty, brave, clever and dangerously determined. The characterization and the character development is incredible and I love the different personalities: We have the mysterious characters, the loving ones, the cruel ones, the bitter ones...and I love the variety!
***
"Let the fish see the bait, not the hook."
***
I was kept intrigued throughout the entire book. Zak's first mission isn't child's play at all and he has to use everything he's learnt to help him succeed. And once the ball started rolling into action, it didn't stop—things just kept happening and it left me at the edge of my seat. There's constant gunfire; there's some snooping; there are deadly threats and the uncovering of secrets. More than once Zak's cover had almost been blown and I wondered how the heck he was going to get out of the situation. But thankfully, Zak is a quick thinker. Of course, things don't always go as planned—but that just makes things all the more interesting.
***
"If you can admit you're scared, that's the first step to controlling it. And if you can't control your fear, it can get in the way of you making the right decisions."
***
Other than the intricate plot, the characters and the amount of suspense and action, the writing in itself was beautiful. I loved the descriptions and all the details in the book. (I didn't even mind the very few grammatical errors.) The diction used wasn't all too complicated, but it wasn't childish either.
***
"It's impossible to say how many men Calaca has killed. Chances are that he doesn't even know himself."
***
And finally, the conclusion. I LOVED it. And that doesn't happen very often. I saw the events of the epilogue coming and for the first time, I'm actually glad my predictions were correct! If there were any other ending, I'd be disappointed because the conclusion was marvelous. And I cannot wait to read the sequel. This was one of the best books I've ever read and I am really, really excited to go on another adventure with beloved Agent 21.
***
"The secret to a successful operation is not to leave anything to chance..."
33 reviews1 follower
February 18, 2022
Quote:
It’s worth remembering that people are not always what they seem.

Too much information can be a dangerous thing.

The best lies are the ones that have an element of truth in them.

People think it [revenge] will solve everything, but life is more complicated than that.



Zak Drake, 13 years old teen living in London, recently became an orphan and currently living with his uncle and aunt. Understandably, he was not welcomed to live with his uncle and aunt. His parents, who were visiting Nigeria as a delegation of a university conference, died in an unexplained mass murder. Six months after their death, Zak met a mysterious man named Michael, who offered him the chance to join a clandestine governmental agency. Michael also told Zak that he knew something about the inexplicable death of Zak's parents. Considering his current situation, Zak agreed to join the agency.

After joining the agency, he was given six months of training. He learned about Morse Code, became fluent in 2/3 different languages, learnt how to handle various weapons, navigate with the help of stars and a few other tricks.

After his training was over, Michael briefed Zak about the most dangerous, wealthy and secured drug lord of Mexico, Cesar Martinez Toledo. A man who had five body-doubles and more security than El Presidente. Zak's mission was to infiltrate Cesar's compound and collect evidence against Cesar Martinez Toledo. If Zak succeeds in his mission only, Michael would reveal the information about Zak's parents' death.


The novel launched itself with a suspense that will hook any reader. The story's plot is simple but full of action and excitement, which will leave the reader turning the pages. I didn't find anything boring in this novel. One thing that was a bit hard for me to digest was that a 13 years old teen-only with six months of training was sent to such a dangerous mission. Overall, Agent 21 was a tremendous teen-spy thriller novel to enjoy. I'm eagerly waiting to read the other novels of this series.
Profile Image for Romana.
536 reviews13 followers
April 24, 2022
4 stars.

(Here are some content warnings. To add: mass murder. Nothing in depth in this review, but will mention loss of parents).

That was solid. Gotta love the kid spies.

Since the unexpected death of his parents 6 months ago, Zak Darke's life has been bleak. Living with his aunt and uncle has him feeling unwanted and unwelcome, and school is unexciting given that he finds most of his lessons too easy. Then he is approached by a mysterious man claiming to solve all his problems and giving him a new purpose, and a new name: Agent 21. Overnight, Zak's life flips to one of challenge and intrigue. And as his first undercover mission approaches, he can only hope that he is ready to face its danger.

These type of books are difficult to write reviews for, because you get what you're given and you say 'thank you very much' and you enjoy yourself. There isn't typically much to unpick, as is the case with Agent 21. It was cool, fun, suspenseful at times, and a fast-paced read. I had a good time.

Zak was a strong protagonist who I warmed to quickly. I thought his reactions to his situation were believable and relevant, whilst his occasional wit made for a nice touch to the otherwise serious tone.

Chris Ryan does well with pacing and attention - things move quickly, and I didn't feel as though I was waiting long for the next step. Even when Zak was going through vigorous training for his new role, things didn't feel repetitive which was a relief.

I will say, though, that I do wish we saw a bit more of Zak's training in action. I wanted to feel as though his gruelling weeks of preparation had truly paid off and a made a difference to his behaviour in the field, but with the exception of shooting ability, I couldn't really see this.

But hey, this book was strong and made for solid entertainment over the past few days. Hats off to Chris Ryan.
Profile Image for Ana Ionite.
49 reviews5 followers
May 10, 2018
I am a passionate reader. So, after many years, I can tell from the very beginning of a book if it s worth it.( money, time spent, my nerves and so on)
Now, on this precise topic, I was thrilled: wow, a book with bio terroristes and a mystery as big as Big Ben!
Charmed.
But it wasn t a 100% what I expected, it was quite surprising. I m not complaining, not at all!
But it s about a 13 years old boy, a teenager, someone here compared him with Alex Ryder.
And his training as an op( the author surely knows first had experience all about it that is to know from a man) and...a few mexican drug lords.
Comme on! From Laos( Africa) we had to jump to Mexico City! Weard.
I was expecting some local authenticity, like mexican food, how they live, dance, something colourfull. But no.
I also expected some original, chilling crimes, those in the book-nothing new under the Sun! They kill the enemy and also his family. No joke.
I wanted to find some kind of revenge over his foster parents, so cold hearted. Zach was an orhpan, he deserved some compasion.
And I wanted to find out more about the hero: he s sharp minded but how much? Till where he ll jump, if he s told Jump!?Some plot only him cad desciphre ...
I dont want to be mean, I enjoyed this book, very much, but I wanted more...lots of taste, feelings.
Profile Image for Linette.
366 reviews2 followers
December 21, 2017
So I gave this four stars?

I have read all of Cherub and a lot of Alex Rider. Yes these other two series have done the plot line first. But then there really only 12 plot lines in all of literature anyway. This got high for this plot line based on style.

What Chris Ryan did was keep the 'dodgy stuff" right down. Cherub is full of the lead character eyeing up girls and having a macho attitude. The author of Cherub balances this with strong female characters but all the "tits and bum" detract from his strong messages. Agent 21 also has no bad language, that was obvious or slapped me in the face.

The other thing that lead this to be a 4 for me was believability. Ryan was in the SAS. He knows his stuff, "A kid with a handgun is too obvious." (My paraphrase) "if you are running away from someone and you're faster than them run in a straight line." (Agent 22, Undercover). The situations are more realistic. He also puts things in the story that the reader can go away and learn if they want to, Morse Code, a star chart, an emphasis on learning other languages.

Yes there is violence, these are spy/thrillers it's part of the genre, but as a reader I didn't feel like that was glorified.

Overall action packed read.
Profile Image for Rachel.
Author 7 books2 followers
January 14, 2019
If you like Alex Rider, you'll probably enjoy this series as it's quite similar.

There is mild language throughout. The story is quite detailed, even up to describing how cocaine is made. I did appreciate the overly detailed gun safety lesson. As a girl who's grown up around guns, it was nice to see an accurate portrayal of how to handle guns. Obviously I wouldn't recommend using this book as a how-to manual, but still.

There are a few cliches, such as Martinez having identical body doubles, the obligatory "If I kill the mass murderer, it'll make me the same as him" and the like.

I'm not sure how I feel about the series' villain. It seems a tad much to believe.

Overall, it's not a bad story, well thought out and thorough. I personally don't see myself continuing the series as there's not much that really stood out to me as great. I would recommend to those who enjoy spy stories.
Profile Image for Kiera McCarthy.
1 review
November 13, 2024
This is the fourth time I’ve read the book, and I still enjoyed every bit of it! I love teen spy novels, and Agent 21 delivers on action and suspense. The story follows 14-year-old Zak Darke, who, after the loss of his parents, is recruited and trained by a secret government organization before being sent undercover to Mexico City.

Chris Ryan's background in the SAS really shines through, giving readers an authentic feel for what these high-stakes missions would entail in real life. If you're a fan of the Alex Rider series, you’ll definitely enjoy this thrilling read!
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