What do you think?
Rate this book
The 39 Clues
The Black Book of Buried Secrets
For the past five hundred years, the Cahills have silently dominated the world. Their desperate hunt for the 39 Clues lies behind some of history’s biggest enigmas – the curse of the Hope diamond, the race to summit Mt. Everest, the wild life and death of Harry Houdini. And now – finally – the secrets are out. With an introduction by Rick Riordan, The 39 Clues: The Black Book of Buried Secrets reveals the shocking truth about history’s most notorious family.
In full, lush color, The 39 Clues: The Black Book of Buried Secrets lays bare each hidden fact, concealed strategy, top agent, lost founder, secret base and hushed-up scandal of the Clue hunt. This complete guide to the Cahills contains information on all five branches, including the notoriously elusive Madrigals. The must-know information includes:
-Full files on the enigmatic Man in Black.
-The true purpose of the Madrigal branch.
-The complete story of the fire that split the original Cahill family.
-The truth about the night Hope and Arthur Cahill died.
-Open access to the secrets of the Lucian, Ekaterina, Tomas and Janus branches.
It’s never too late to join the hunt – especially with The 39 Clues: The Black Book of Buried Secrets to provide complete access to the Cahill’s most deeply-buried secrets.
http://www.scholastic.com/kids/39clues/
http://www.the39clues.com/
In full, lush color, The 39 Clues: The Black Book of Buried Secrets lays bare each hidden fact, concealed strategy, top agent, lost founder, secret base and hushed-up scandal of the Clue hunt. This complete guide to the Cahills contains information on all five branches, including the notoriously elusive Madrigals. The must-know information includes:
-Full files on the enigmatic Man in Black.
-The true purpose of the Madrigal branch.
-The complete story of the fire that split the original Cahill family.
-The truth about the night Hope and Arthur Cahill died.
-Open access to the secrets of the Lucian, Ekaterina, Tomas and Janus branches.
It’s never too late to join the hunt – especially with The 39 Clues: The Black Book of Buried Secrets to provide complete access to the Cahill’s most deeply-buried secrets.
http://www.scholastic.com/kids/39clues/
http://www.the39clues.com/
189 pages, Hardcover
First published October 26, 2010
66 people are currently reading
5092 people want to read
Ratings & Reviews
Friends & Following
Create a free account to discover what your friends think of this book!
Community Reviews
Displaying 1 - 30 of 170 reviews
November 16, 2011
When I finished this book, all I could think was, "This is The 39 Clues version of The Demigod Files." And I say that as a good thing. It was a great way to reacquaint oneself with the major players before the Cahills vs Vespers series starts, plus is a great jumping off point for learning more about certain figures in history. Now, as far as I know, there is no great family of Cahills that have been maneuvering the world for 500 years (and if there was, since I'm not a Cahill, I wouldn't know, would I?). But it is interesting to think what various historical figures would have done in their search for the clues. (I don't think it's been addressed, but I could imagine Agatha Christie's disappearance would have been because of a clue hunt.)
It's a good book for when you have short bursts of time in which to read. Each part is only a few pages long, yet it still packs a ton of information into each bit without it feeling overwhelming. Like I've said in the past, I think the 39 Clues series is a great one for getting kids interested in history and historical figures. It tells just enough about them to whet the appetite and leave kids (and adults) anxious for more. I've got several people that I don't remember hearing about that I'm going to be reading up on thanks to this book.
There were two parts of this book that I enjoyed above all others - the introduction, written by Rick Riordan and telling the story of the first face to face meeting of the Cahills responsible for putting the story of the 39 Clues out there in the hopes of protecting Amy and Dan. It was a fun read and I loved having a different look at the authors.
The other were the agent reports. Written as short vignettes rather than factual information blurbs, it helped bring the reader back into the world of the 39 Clues very easily. But then again, I really like good fiction.
I would definitely suggest waiting until after you've read the first ten books before picking up The Black Book of Buried Secrets, unless you don't mind being spoiled. It doesn't give away every little bit but it does have some pretty major spoilers throughout. It's not a necessity to read before you start the Cahills vs Vespers series, but I do think you would thank yourself for reading it.
It's a good book for when you have short bursts of time in which to read. Each part is only a few pages long, yet it still packs a ton of information into each bit without it feeling overwhelming. Like I've said in the past, I think the 39 Clues series is a great one for getting kids interested in history and historical figures. It tells just enough about them to whet the appetite and leave kids (and adults) anxious for more. I've got several people that I don't remember hearing about that I'm going to be reading up on thanks to this book.
There were two parts of this book that I enjoyed above all others - the introduction, written by Rick Riordan and telling the story of the first face to face meeting of the Cahills responsible for putting the story of the 39 Clues out there in the hopes of protecting Amy and Dan. It was a fun read and I loved having a different look at the authors.
The other were the agent reports. Written as short vignettes rather than factual information blurbs, it helped bring the reader back into the world of the 39 Clues very easily. But then again, I really like good fiction.
I would definitely suggest waiting until after you've read the first ten books before picking up The Black Book of Buried Secrets, unless you don't mind being spoiled. It doesn't give away every little bit but it does have some pretty major spoilers throughout. It's not a necessity to read before you start the Cahills vs Vespers series, but I do think you would thank yourself for reading it.
November 29, 2010
wow that book is THE BOMB!!! They make it sound so real! Wonderful, splendid, awesome, and a genius book!!!
February 3, 2019
This book make everything sound so real. I love it
May 5, 2025
the intro imagining that all the authors of the OG series were cahill agents is just... so iconic lol
May 31, 2011
A companion book to the popular 39 Clues series, The 39 Clues: The Black Book of Buried Secrets is a good bet, not only for the series' most die hard fans, but for those of us seeking some closure to a few of the threads left dangling at the end of The 39 Clues, Book 10: Into the Gauntlet. The book answers some questions, forces us to ask a few new ones, dangles a few new mysteries in our faces and gives us a chance to catch up with several of the series' major players since Gauntlet's end.
Touted as the "ultimate guidebook" to the 39 Clues world, this is also a full color reference book to the fictional Cahill family, their various branches and to the history, famous historical members, founders and current agents of each branch. Information on branch strategies, strengths and strongholds, etc. is nicely laid out and more fun to read than I expected it to be. Author Rick Riordan, who wrote the first book in the 39 Clues series as well as the overall series arc has given us an attractive and interesting series overview that I'm happy to add to my collection even though I consider the "ultimate guidebook" description to be just a bit of a stretch.
The Black Book of Buried Secrets also serves as a bridge to - wouldn't you know it? - a new 39 Clues series set to launch in April, 2011 with The 39 Clues: Vespers Rising, the first volume in The 39 Clues: Cahills vs. Vespers. In the new series, the Cahills will have to band together to protect their secrets from the Vespers, another large (and reportedly quite evil) family who have been watching the Cahills for years and are determined to uncover and steal the sources of their power. After Vespers Rising, the series consists of six additional books that will be published between August 2011 and March 2013 from authors Gordon Korman, Jude Watson, Peter Lerangis, Roland Smith, Linda Sue Park and (!!) David Baldacci.
Recommended.
Minor & Totally Personal Quibble: As someone who only read the books and wasn't involved with the website or the cards that were parts of the 39 Clues world, I hadn't come across the photos of the characters before and I have to say, I'm not a real fan of them. I guess I prefer the images my own mind created of Dan & Amy (and everyone else) and that preference made the photos somewhat distracting for me. But, like I said, a minor quibble.
Touted as the "ultimate guidebook" to the 39 Clues world, this is also a full color reference book to the fictional Cahill family, their various branches and to the history, famous historical members, founders and current agents of each branch. Information on branch strategies, strengths and strongholds, etc. is nicely laid out and more fun to read than I expected it to be. Author Rick Riordan, who wrote the first book in the 39 Clues series as well as the overall series arc has given us an attractive and interesting series overview that I'm happy to add to my collection even though I consider the "ultimate guidebook" description to be just a bit of a stretch.
The Black Book of Buried Secrets also serves as a bridge to - wouldn't you know it? - a new 39 Clues series set to launch in April, 2011 with The 39 Clues: Vespers Rising, the first volume in The 39 Clues: Cahills vs. Vespers. In the new series, the Cahills will have to band together to protect their secrets from the Vespers, another large (and reportedly quite evil) family who have been watching the Cahills for years and are determined to uncover and steal the sources of their power. After Vespers Rising, the series consists of six additional books that will be published between August 2011 and March 2013 from authors Gordon Korman, Jude Watson, Peter Lerangis, Roland Smith, Linda Sue Park and (!!) David Baldacci.
Recommended.
Minor & Totally Personal Quibble: As someone who only read the books and wasn't involved with the website or the cards that were parts of the 39 Clues world, I hadn't come across the photos of the characters before and I have to say, I'm not a real fan of them. I guess I prefer the images my own mind created of Dan & Amy (and everyone else) and that preference made the photos somewhat distracting for me. But, like I said, a minor quibble.
December 4, 2012
This is a book about the Cahills who are a family that are searching for 39 clues which will make them very powerful. In this book it just tells you about their lives and secrets in their families. This book is a basically a biography on the Cahills and their best agents.
I think they did good on describing everyone's thought and emotions. THey also explained each agent well. I think they could have improved on the stories and described the a little better.
I liked the book because it told me a lot more aout eh characters in the series. I would recommend it to people who have read the first book of the 39 Clues because if you haven't you wont know who each character is. You have to know the protagonist and the antagonist before you read this book. YOu also need to have a basic understanding of the book. Overall, I really enjoyed this book.
I think they did good on describing everyone's thought and emotions. THey also explained each agent well. I think they could have improved on the stories and described the a little better.
I liked the book because it told me a lot more aout eh characters in the series. I would recommend it to people who have read the first book of the 39 Clues because if you haven't you wont know who each character is. You have to know the protagonist and the antagonist before you read this book. YOu also need to have a basic understanding of the book. Overall, I really enjoyed this book.
March 25, 2011
I liked it cause it kinda gave you more information behind all the other books and what has happened to some of the characters since the ending of the 10th book. But it didnt have that appeal to keep reading.. I finished it more along the lines of okay so this might be helpful for the next book...and once I start a book it is hard for me to NOT finish it.. It has to really really suck OR scare me..lol
November 24, 2015
This book is the secrets of all the branches in the Cahill family in order to save their branches.I liked this book because Rick put the secrets in the open and I know everything about the Cahill branches without reading the other books to find out.I would recommend this book to people who like shortcuts and others who like The 39 Clues.
Want to read
June 21, 2010Sounds like this is a full explanation of everything you could want to know in the whole series. I'm looking forward to this one!
February 19, 2011
☻ Go Lucians!
Currently reading
February 2, 2011i think it is fun book because it is fun to solve mysteries
September 14, 2011
Cool book. I loved how the winners of the game were included as characters in the beginning. It makes it all seem more real.
December 31, 2023
A few real life people are listed as agents for each branch. I wish they were more well know. Especially since this series is meant for middle school is age kids. They won’t know who these computer geniuses are
I love how detail is even paid to the background. Each branch section is not only colored with their color, but there is also a watermark on the pages that correlate to the branch. Outline of a basketball court, grid paper, and sheet music!
- The authors were agents concealing research as children’s fiction
- None of the authors are tomas
- Recruited online players
- Madrigals are meant to maintain balance. Not any single branch should learn ALL the clues
- Founded organizations like red cross to balance damage from the hunt
- Hope became an archeologist to travel the world without suspicion
- Arthur was a vesper!!?
- Madrigal agents include double agents originally from other branches
- Madrigals let in an imposter which made entering the branch much harder
- Amy and dan visit their parents graves and find a vial of vinegar (one of the clues) with engravings
- Barack obama is a lucian
- Lucians dominate politics and wage wars
- Lucians include gustave eiffel and a judge during the witch trials
- Isabel’s trial
- Ekat dragon symbolizes creativity, inventiveness, intelligence, and willingness to destroy anything in their way
- Thomas knew katherine would take his clues. He left one and took the rest of his
- Lucian branch leaders pick their successor. Ekats are passed down in the family. Tomas nominate themselves then compete in something like the olympics
- Hideyoshi was Thomas’s son!
- The holts are hated by their branch because Eisenhower’s father was believed to be a traitor
- Eisenhower and Arthur were roommates!
- A tomas almost discovered a madrigal stronghold. Before, no one got within 2,000 miles
- Tomas clues are usually hidden in places most people can’t reach
- West point cadets are nominated by congressman which is hard when most are lucians
- Janus typically have 3 leaders at once in case one has a spark of creativity and focuses on their art
- Mozart spend money searching for the clues. Died penniless. Bones were lost when graveyard was rearranged
- Jonah does mtv cribs
- Had an 8 hour surgery to fix his leg
Unless you looked at each and every inch of this book, i doubt any single person could find all the hidden clues without help.
There was a mention of using scoreboard messages. There is a picture on a scoreboard with miscellaneous letters and number. Capital and lowercase. I highly doubt that is not a clue
I love how detail is even paid to the background. Each branch section is not only colored with their color, but there is also a watermark on the pages that correlate to the branch. Outline of a basketball court, grid paper, and sheet music!
- The authors were agents concealing research as children’s fiction
- None of the authors are tomas
- Recruited online players
- Madrigals are meant to maintain balance. Not any single branch should learn ALL the clues
- Founded organizations like red cross to balance damage from the hunt
- Hope became an archeologist to travel the world without suspicion
- Arthur was a vesper!!?
- Madrigal agents include double agents originally from other branches
- Madrigals let in an imposter which made entering the branch much harder
- Amy and dan visit their parents graves and find a vial of vinegar (one of the clues) with engravings
- Barack obama is a lucian
- Lucians dominate politics and wage wars
- Lucians include gustave eiffel and a judge during the witch trials
- Isabel’s trial
- Ekat dragon symbolizes creativity, inventiveness, intelligence, and willingness to destroy anything in their way
- Thomas knew katherine would take his clues. He left one and took the rest of his
- Lucian branch leaders pick their successor. Ekats are passed down in the family. Tomas nominate themselves then compete in something like the olympics
- Hideyoshi was Thomas’s son!
- The holts are hated by their branch because Eisenhower’s father was believed to be a traitor
- Eisenhower and Arthur were roommates!
- A tomas almost discovered a madrigal stronghold. Before, no one got within 2,000 miles
- Tomas clues are usually hidden in places most people can’t reach
- West point cadets are nominated by congressman which is hard when most are lucians
- Janus typically have 3 leaders at once in case one has a spark of creativity and focuses on their art
- Mozart spend money searching for the clues. Died penniless. Bones were lost when graveyard was rearranged
- Jonah does mtv cribs
- Had an 8 hour surgery to fix his leg
Unless you looked at each and every inch of this book, i doubt any single person could find all the hidden clues without help.
There was a mention of using scoreboard messages. There is a picture on a scoreboard with miscellaneous letters and number. Capital and lowercase. I highly doubt that is not a clue
This entire review has been hidden because of spoilers.
December 26, 2025
#BernardReads | BOOK REVIEW 📚
#The39Clues: The Black Book of Buried Secrets by Mallory Kass 📓
I decided to follow the publication order as my reading order as well. So before I delved into Book 11 which serves as a bridge to the next series, I wanted to devour this companion book which I was tempted to read even before I started the series. It’s a dossier of almost all secrets and facts about the Cahill family.
It had an introduction by Uncle #RickRiordan which made me more excited. It was framed as a meeting among the first series authors deciding to share their secrets here. It was super awesome. If I read this when I was younger, this could be my favorite book of all time. Uncle Rick is so good on making fiction super realistic and imaginative. I have to say it like that because I may have shut up by secret organizations.
I also tried the online game like 15 years ago? It bummed me that it was down now. I wanted to revisit it. So guys, please support the ongoing graphic novel adaptations and maybe show adaptation in the future.
First of all, I like the format. There were information reveals here which I believed might have spoiled me before reading the next books. Idk, this was available first to readers before them. I just followed the order. Nevertheless, they were juicy information that I hoped could still add to a more positive reading experience for me.
The collection of pictures was great as well. This is before generative AI so I appreciate a lot of effort put into this.
It also has some entries that somehow revisits our characters. They were a delight. And almost every page was ridden by clues I hardly caught up.
And after reading the whole book, I believe I am ready to tackle the Cahill’s next adventures against the Vespers!
#bookrecommendations #bookreview
#The39Clues: The Black Book of Buried Secrets by Mallory Kass 📓
I decided to follow the publication order as my reading order as well. So before I delved into Book 11 which serves as a bridge to the next series, I wanted to devour this companion book which I was tempted to read even before I started the series. It’s a dossier of almost all secrets and facts about the Cahill family.
It had an introduction by Uncle #RickRiordan which made me more excited. It was framed as a meeting among the first series authors deciding to share their secrets here. It was super awesome. If I read this when I was younger, this could be my favorite book of all time. Uncle Rick is so good on making fiction super realistic and imaginative. I have to say it like that because I may have shut up by secret organizations.
I also tried the online game like 15 years ago? It bummed me that it was down now. I wanted to revisit it. So guys, please support the ongoing graphic novel adaptations and maybe show adaptation in the future.
First of all, I like the format. There were information reveals here which I believed might have spoiled me before reading the next books. Idk, this was available first to readers before them. I just followed the order. Nevertheless, they were juicy information that I hoped could still add to a more positive reading experience for me.
The collection of pictures was great as well. This is before generative AI so I appreciate a lot of effort put into this.
It also has some entries that somehow revisits our characters. They were a delight. And almost every page was ridden by clues I hardly caught up.
And after reading the whole book, I believe I am ready to tackle the Cahill’s next adventures against the Vespers!
#bookrecommendations #bookreview
May 2, 2024
After the 39 Clues finale, a new threat has arisen, leading the separate branches of the Cahill family to come together and share their secrets. Broken down into a section for each of the 5 branches, this book covers founders and agents (though I'm not 100% sure what the difference is, since some of the founders are current...how can they be founders 500 years after the branch was founded?), strongholds, and tools and tricks used by each branch. It's a good follow-up to the series, with some reminders of locations, names, or events that were brought up during the series, as well as new information. The brief vignettes that show some of the major characters from the series after the end of the clue hunt were great to have, and there are even a couple of short stories about historical characters looking for clues or being recruited by Cahills. There are a few things explained in this book that I at first thought must be spoilers of what is technically the final book in the series, though also a launching point for the first spin-off series. That book was published after this one, so I hope that's not the case, but I won't know until I read it (Vespers Rising).
The introduction by Rick Riordan, which depicts the different authors from the series as members of the Cahill branch, meeting to discuss sharing their secrets for this book, is clever and enjoyable. Fans of the 39 Clues series will probably find the brief stories and extra information in this book worth reading.
The introduction by Rick Riordan, which depicts the different authors from the series as members of the Cahill branch, meeting to discuss sharing their secrets for this book, is clever and enjoyable. Fans of the 39 Clues series will probably find the brief stories and extra information in this book worth reading.
May 26, 2025
Growing up, I loved the 39 clues series. Loved as in LOVED! Reread it every summer (and maybe again during the school year??) Sadly, it has been several summers since I’ve read the series, but I’ve still got them with me! Since I thrifted this Black Book of Secrets, I knew I’d be returning to the hunt soon enough.
This book was so much fun, both in the forward by RR which plays into the world of the 39 clues, along with the content itself. I can see how reading this right after finishing the series would be a ton of fun when you have everything fresh in your head! For me, it was moment after moment of “oh yeah! That person” or “haha yeah they almost died there” etc. (Yes, I even forgot a somewhat large twist and reading the names in this reminded me… oops!)
You get a variety of definitely-very-true facts about the Cahill family branches, and insight to their different members, current agents, special tools, some flashback/story elements, and locations of bases. (Anyone else inspired to make a worldwide vacation/tour of different clue spots??)
Fun for tweens/teens if it’s their first time, or for us oldies feeling a bit nostalgic!
4⭐️ loved it, will read again!
Happy reading ♥️📚
This book was so much fun, both in the forward by RR which plays into the world of the 39 clues, along with the content itself. I can see how reading this right after finishing the series would be a ton of fun when you have everything fresh in your head! For me, it was moment after moment of “oh yeah! That person” or “haha yeah they almost died there” etc. (Yes, I even forgot a somewhat large twist and reading the names in this reminded me… oops!)
You get a variety of definitely-very-true facts about the Cahill family branches, and insight to their different members, current agents, special tools, some flashback/story elements, and locations of bases. (Anyone else inspired to make a worldwide vacation/tour of different clue spots??)
Fun for tweens/teens if it’s their first time, or for us oldies feeling a bit nostalgic!
4⭐️ loved it, will read again!
Happy reading ♥️📚
July 5, 2023
📖El libro negro de los secretos enterrados📖
Ok ok, aun no inicia la 2da Saga de las 39 pistas.
Este libro es una recopilación de hechos e información de los personajes, las ramas e incluso introducen qué los autores de las 39 pistas también son Cahill (Eso está muy divertudo😅)
Bueno, al darnos un poco de información adicional tenemos unos Plots Twist muy interesantes, y tenemos la conclusión de algunos casos (como. Los asuntos de la familia OH).
También nos ponen un poco en contexto como se tomaron las demás ramas el resultado de la caceria (y dan ganas de machacarlos, los chicos no pudieron obrar mejor que en aquel momento).
Y nos introducen a la próxima amenaza, una organización llamada VESPERS🤩🤩🤩
Justo después de la conclusión en la Fortaleza Madrigal, salieron 2 libros para hacer nexo entre la primera y la segunda Saga: Un libro es éste el de los segretos enterrados y el otro es el Surgimiento de los Vespers.
Ya leímos el libro de los archivos Cahill ahora vamos a conocer a los Vespers 🤩🤩
I cant wait
Ok ok, aun no inicia la 2da Saga de las 39 pistas.
Este libro es una recopilación de hechos e información de los personajes, las ramas e incluso introducen qué los autores de las 39 pistas también son Cahill (Eso está muy divertudo😅)
Bueno, al darnos un poco de información adicional tenemos unos Plots Twist muy interesantes, y tenemos la conclusión de algunos casos (como. Los asuntos de la familia OH).
También nos ponen un poco en contexto como se tomaron las demás ramas el resultado de la caceria (y dan ganas de machacarlos, los chicos no pudieron obrar mejor que en aquel momento).
Y nos introducen a la próxima amenaza, una organización llamada VESPERS🤩🤩🤩
Justo después de la conclusión en la Fortaleza Madrigal, salieron 2 libros para hacer nexo entre la primera y la segunda Saga: Un libro es éste el de los segretos enterrados y el otro es el Surgimiento de los Vespers.
Ya leímos el libro de los archivos Cahill ahora vamos a conocer a los Vespers 🤩🤩
I cant wait
August 21, 2022
A wonderful collectible book that has information on all branches of the Cahill family along with snippets of the lives of a few agents throughout time.
It does serve for minor spoilers here and there, though, so I'd personally keep it for after Cahills vs Vespers. It makes more sense after the events anyway, as far as I can tell.
There's a neat little introduction by Rick Riordan which manages to personify all the authors as Cahills. The book itself is beautiful with the cover being rough paper with engravings in shiny silver and the pages complete with numerous illustrations and immersive artwork and backgrounds all printed on thick photo paper.
It's definitely collector's book, but it sure is a fine one at that.
It does serve for minor spoilers here and there, though, so I'd personally keep it for after Cahills vs Vespers. It makes more sense after the events anyway, as far as I can tell.
There's a neat little introduction by Rick Riordan which manages to personify all the authors as Cahills. The book itself is beautiful with the cover being rough paper with engravings in shiny silver and the pages complete with numerous illustrations and immersive artwork and backgrounds all printed on thick photo paper.
It's definitely collector's book, but it sure is a fine one at that.
October 17, 2019
The book the 39 clues and the black book of buried secrets I thought was a good book it gave a lot of interesting facts and it talks about a lot of secrets about the world and it also has a mission for you that is super top secret and is only in the hands of someone good and it's a mystery for those who will find the 39 clues first you or the characters. And you go through mysteries and you have to solve them and when you get all 39 clues you win and find out what the 39 clues are all about. I think people who like mysteries and finding out things would love this book.
October 17, 2024
As a true completionist at heart I felt like I had to seek out and give this a fair read through. Mostly due to it being a lot of small stories, advice, inventions and some interviews it both felt like a tad more fun being added to the overall storyline but even with that, it couldn’t help but feel a little unnecessary and kind of just a fact collections books which isn’t bad but isn’t fantastic either.
March 15, 2020
I loved reading all the viewpoints as well as learning more about each branch! The Madrigals aren’t quite as mysterious as they once were! This book is really interesting and action packed in ways I didn’t expect!
September 29, 2023
This was a delight - nothing could have prepared me for an introduction that's a self-insert fanfiction featuring Rick Riordan meeting with the other authors of the books ... reading that the Lucians use "spy monkeys" ... seeing Natalie's stupid outfit... good stuff all around.
May 24, 2024
Says so much about the whole series, if you read them all. Very informative and tells you all about the secret 5th branch of the Cahill family, the Madrigals. The plot is so good, even though it’s the end of the series. Highly would recommend!!
This entire review has been hidden because of spoilers.
May 26, 2025
A supplemental book to the series, information about the Cahill branches and the characters and historical figures, etc claimed by each.
Do NOT read until after the other books as it contains references that can be spoilers for book 10’s conclusion.
Do NOT read until after the other books as it contains references that can be spoilers for book 10’s conclusion.
May 17, 2017
i love that it tells me who the people are and what branch they ae in
November 20, 2017
this book enplanes a lot about the cahill famously and some stuff I did not understand in the books seirys
March 2, 2018
Adds more depth to the story, but nothing overly necessary. Still interesting though.
February 19, 2020
4,1/5,0
May 25, 2020
Amazing! This introduction to the 39 Clues tells me what a Clue is and how the Cahills find them.
March 15, 2021
it can be considered an encyclopedia of the series,i do like the design and also the puzzles in the book.
Displaying 1 - 30 of 170 reviews