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US Marshals: Task Force 9 #2

Cipher: Lethal Algorhithm

A legendary hacker on the run. A dominant US Marshal sent to capture her. One island safe house.

You've spent three years running from the monsters who burned your life to the ground — and now the only safe place left to hide is in the arms of the man sent to capture you.

Ivy is a ghost. The legendary hacker known as "the dragon," she survives on cold logic, burner laptops, and one steel-clad rule: never leave a footprint. She burns the Consortium's financial networks to make them pay for the friend they stole from her, and she never stays anywhere long enough to let the world touch her. Until a high-stakes zero-day in Macau goes wrong, and she's cornered in a dark parking garage.

Enter Julian Rhodes. US Marshal. Task Force 9 — the off-books federal unit that handles the targets who don't exist. He's spent eleven weeks tracking a shadow, and he isn't about to let her slip. Cocky, controlled, and hyper-confident, Julian lives to own the room. But when he finally captures his target, he doesn't find a cold corporate threat. He finds a sharp, defensive genius whose isolation trips every protective instinct he's spent his career locking down.

Forced into proximity in a remote island safe house, they run a joint extraction against a degrading seventy-two-hour window. His steady, load-bearing calm meets her razor-fast digital shields, and the friction sparks a heat neither can control. Under his roof, Julian gives her something she's never let herself have — the grounding safety she's been starved for since the day she ran.

Then a brutal ambush compromises their extraction, and Ivy makes the ultimate play to keep him alive: she cuts him out, secures the drive, and vanishes into the cold Shinjuku rain.

Julian doesn't take abandonment lightly. He survived the crossfire, and he's crossed an ocean to bring his ghost home — a digital trap built to catch her one-of-a-kind signature, waiting for the moment she slips. Because once you surrender to a protector, he never lets you run again.

214 pages, Kindle Edition

First published August 4, 2026

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About the author

Ellie Masters

156 books1,670 followers
Angsty, Steamy, Heart-Stopping, Pulse-Pounding, Can't-Stop-Reading Romantic Suspense.

Ellie Masters is a USA Today Bestselling author and Amazon Top 15 Author.

In addition, she's a wife, military mom, doctor, and retired Colonel.

She writes romantic suspense filled with all your sexy, swoon-worthy alpha men. Her writing will tug at your heartstrings and leave your heart racing.

Born in the South, raised under the Hawaiian sun, Ellie has traveled the globe while in service to her country. The love of her life, her amazing husband, is her number one fan and biggest supporter. And yes! He's read every word she's written.

Don't forget to sign up for her newsletter. Never miss another release, sale, or exclusive. https://elliemasters.com/NewsletterSi...

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5 stars
324 (65%)
4 stars
122 (24%)
3 stars
41 (8%)
2 stars
8 (1%)
1 star
1 (<1%)
Displaying 1 - 30 of 39 reviews
Profile Image for Carol.
3,726 reviews3 followers
August 10, 2026
Cipher:Lethal Algorithm

This story is so intense and full of drama and suspense, not sure who you can trust. The people who have the skill to hack into those that are evil, corrupt and are doing things government is trying to get enough on to shut them down. When Julian is trying to get to Ivy To keep her safe, it’s all they can do to keep out of the way of those hunting them. This story of true warriors to keep each other safe, and their team. Awesome story
8 reviews
August 5, 2026
Another fantastic book by Ellie Masters.Just like the Cerberus series,this series also tracks a Consortium with all the suspense,close proximity,an unwavering touch her and die alpha protector,a hacker with trust issues and scorching heat.Absolutely recommended with 5 stars.Now waiting (not so) patiently for Wraith...
Profile Image for Nickie Sale.
971 reviews8 followers
August 14, 2026
Cipher: Lethal Algorithm by Ellie Masters is the 2nd in the Task Force 9 series and once again Ellie has blown me away with an intense and emotional romance. Ivy is a legendary hacker known the Dragon. Julian is Task Force 9’s hyper competent tech guru known as Cipher.

Ivy has spent 3 years obsessed with burning to the ground the financial networks of the Consortium, the syndicate that murdered her friend. All that time she’s been running, never staying anywhere long enough to be found. Julian has been tracking Ivy for quite a while, chasing her digital shadow. He expects to find a cold corporate hacker, instead he finds a razor sharp, brilliant woman whose isolation hits him straight in the chest and you immediately feel this instant chemistry, the sparks flying between them, that’s sharp, dangerous and undeniable between them.

The technology whizzing around in Cipher is enough to put even the most tech savvy of us into a complete tailspin, but that almost pales into insignificance with Ivy & Julian’s journey is action packed and dangerous with a forced proximity that matters and emotional intimacy without rushing. Their romance is a chase that becomes a love story and a beautiful pairing, much like her yin to his yang. Ivy has never had safety, Julian becomes her first taste of it, he gives her grounding, she gives him purpose. They fall — quietly, intensely, inevitably, they choose each other in a romance built on safety, partnership, trust and a future where she stops being a ghost and doesn’t have to run and a life where he stops being alone and doesn’t have to chase.

Profile Image for Roxs Reads.
862 reviews1 follower
Review of advance copy received from Author
August 2, 2026
I'm loving the U.S. Marshals series. New threats to take down and new heroes to fall in love with. Legal Algorithm: Cipher is suspenseful and had me on edge to the very end.

Julian and Ivy are the perfect love match. Geniuses in their own right; their cyber knowledge blew me away, when it wasn't confusing the shit out if me, LOL! There is a lot of computer geek talk, but it all amazed me. Their love of the cyber world took center stage, and then they took that passion to the bedroom. Well, when they made that far!

Sweet and loving isn't how I'd describe this couple. They were all about getting to the endzone, whether in the trenches of the dark web, or in their need for physical release. They were both on the same page, and it made for some fantastic reading.

Not surprisingly, author Ellie Masters has delivered another 5-star story. I noticed a significant change to her writing with this book, for the better. I loved how improved her descriptive language was and the sentences were cleaner, leaving out those pesky filler words. I never tire of her writing and I look forward to book #3.
1,264 reviews5 followers
August 9, 2026
Hiding for 3 years in isolation, Ivy is determined to bring down the Consortium the only way she knows how, through her computer. Julian, Cipher, is sent to get the device that Ivy holds, a device that can help to bring down the Consortium. Expecting a hardened hacker, he discovers a ghost that has a reason for her actions, a woman who he wants to protect. Together they are unstoppable, a couple whose love language is computer algorithms, apart, they discover a loss they never knew existed and Julian will use his skills to again track down the woman who left to preserve his life following an ambush.

Another fantastic addition to this new series about Task Force 9. The suspense and drama starts from the first page and carries you throughout on a rollercoaster with all the twists and turns. Their chemistry sparks from their first encounter online and I love how their passion is as fierce as their determination to stop the Consortium. I can't wait to read Wraith's book as I suspect there will be more explosive revelations within it.
Profile Image for Melanie.
4,343 reviews33 followers
August 4, 2026
Wow! Where to start? Cipher is full of suspense and intrigue with some danger mixed in. And, yes there is a steamy romance sizzling under it all. But the emphasis here is on cyber warfare. Julian "Cipher" Rhodes, US Marshall is smart, savvy, determined and one of the best in his tech field. He may met his match in Ivy. He's been tracking her work for months before he finally finds her. She"s spent three years trying to right a wrong. She's equally adept at coding, getting in and out of networks without being caught and building traps. Together they take on something/someone bigger and more influential than they suspected. The attraction between them is palpable but she's not big on trust. He's wanted her fron the outset. He becomes her partner and protector. I cheered for them start to finish. Another stellar outing from Ellie Masters, not that I expected anything different. Thoroughly enjoyable!
635 reviews7 followers
August 10, 2026
CIPHER and Ivy

I am loving this series. This is the 2nd book in the series. The story revolves around Julian and Ivy. Julian is a U.S. Marshall. He is basically responsible for keeping his teammates safe by finding anything hidden in the digital world before his team gets to their assigned "jobs". Ivy is a self taught brilliant hacker. She grew up in the foster care system and has serious trust issues. I can't begin to tell you how much I enjoyed reading this book. It has literally everything you could want in a story. Intrigue, a bit of danger, suspense, and action so intense you feel like you're in the story. The attraction between Julian and Ivy is off the charts. They have a lot of issues to work through to get the HEA they deserve. Get this book and find out what happens. Sorry, no spoilers. Definitely would recommend.
Profile Image for Shirley.
946 reviews2 followers
August 11, 2026
ONE WORD ... INTENSE..
Exciting story , Ivy and Julian’s story is fast moving and keeps you engaged,I AM SO NOT COMPUTER SAVVY SO TRYING TO UNDERSTAND EVERYTHING ...(mind blowing) however even when you have to put it down,to do certain things at home LOL .... you want to get back to it.
There's ,lot of complicated computer jargon used .... yet you can kinda get the plot they are trying to stop evil peoples.......
Some where along the way they find a Passion for one another ... then when it seems all is done IVY flee's ... she doesn't walk away, she runs away... Thankfully Julian is a smart , sharp cookie... LOVE PREVAILS and sets a trap to find her because he knows she won't resist............VERY AWESOME READING AND INTENSE ..... I AM SO READY FOR THE NEXT STORY in the series!.... HAHAHA NOT SO :) patiently for Wraith
3,068 reviews35 followers
Review of advance copy received from Author
August 2, 2026
These two, Julian and Ivy were such a great match. Their commonalities were in the same vein and I enjoyed that similarity right from the start.

Hacker Ivy was trying to bring down the Consortium, when US Marshall Julian Rhodes tracks her.

I really loved the way Julian could be smug, arrogant, but soft and forthright. Especially to Ivy. Yet she was super smart and switched on to what they wanted to do yet she been trying to do for the years single handedly.

I also deeply respect the expertise and research that went into the story. Totally above the mark so kudos for that Ellie.

The romance was deep, the plot exciting and the elements of suspense always there. So good, terrific actually!
2,112 reviews
Review of advance copy received from Author
August 3, 2026
I cannot imagine how soul destroying it must be to spend three years in virtual isolation, but that is what Ivy did in her quest to destroy the Consortium. I must confess that most of the technical computer language goes right over my head, but the essence of it is amazing. This is a story so full of tension, verging on desperation and heart stopping action, especially once Julian finds her. There are moments that brought tears to my eyes and dialogue that made me smile. A book that is really hard to put down even when falling asleep, but who needs sleep when there is a story to finish! Ivy will find a place in your heart and make you want to hold her tight and that is just what Julian does.

213 reviews6 followers
Review of advance copy received from Author
August 3, 2026
Arc review. CIPHER: Lethal Algorithm (US Marshals: Task Force 9 Book 2) is typical of Ellie Masters in many ways but unbelievably high tech. Julian and Ivy are unmatched at what they do, Ivy hacks and Julian protects but their common goal is to destroy the Consortium. Their chemistry builds slowly as they work together to find the high ranked person behind it all. When the case erupts their relationship does too. Ivy will give up Julian to make sure he is safe while Julian searches for as he can’t live without her. This is an action packed page turner with two people who work to not only keep their world safe but to find their HEA.
189 reviews
August 11, 2026
First, I am not a tech person! My computer laughs at me most of the time, yet somehow I was able to easily follow this story from beginning to end. I absolutely loved Julian (Cipher), he is the kind of guy that just melts your heart. He is all in, there is no hesitation when it comes to him. Ivy is more complicated!! She is so use to being alone and depending on only herself that she really doesn't let people in. She didn't stand a chance against Cipher once he set his mind and heart on her! This book is packed full of action, intrigue,heart stopping moments and lots and lots of heart melting heat between Cipher and Ivy! You will love this one!!
Profile Image for Gazelle.
1,052 reviews11 followers
September 10, 2026
I need to go back to read book one in this series, but I have to say I really enjoyed this. It was a lot of action and suspense. Ivy and Julian were both fluent in programming/hacking which turns out to be something they are both good at. He is willing to put it all on the line to protect Ivy. Nothing matters if they aren't together! She runs but he won't let her go without a fight which is good because she really didn't want to be let go. I started book 3 soon after I really enjoyed them in that one too.
1,745 reviews13 followers
August 4, 2026
A fast action thrill read as Ivy and Julian try to outsmart and out-code the Consortium. Danger has followed Ivy for the last three years as she has tried to dismantle the Consortium finances using her unique hacking skills. Enter US Marshall Julian who has been searching for her for weeks. Together they are a lethal force against the bad guys. Romance blossoms in adversity and this is an enjoyable romantic adventure.
Profile Image for Linda.
1,060 reviews2 followers
August 10, 2026
Alpha Gritty & Hot 🔥

It starts with computer jargon I don’t get, but Ellie makes it easy to flow through. A couple of hackers walk into a room.. no wait 😂 This is a fantastic story about a US Marshal and a woman hacker trying to bring down the bad guys. Intense, exciting, slow burn that explodes into hotness. Ellie’s a one-click author for me. I’m always excited to read her words. 🤓
Profile Image for Sue Smith.
834 reviews7 followers
August 11, 2026
What a thrilling and exciting, fast-paced series this is turning out to be.
I absolutely loved Julian and Ivy wonderful story and can't wait for the next one!
Working alone for 3 years, Ivy found it difficult to trust anyone, even though Julian was as knowledgeable about coding as she was!
Can she help the US Marshalls bring down the Consortium?

I received an ARC copy of this book from the author, and I'm willingly leaving an honest review.
155 reviews
August 14, 2026
Too technical

I've read and love every one of Ellie's books but this was hard. Maybe because I'm one of her much older readers and a bit of a technophobe, but found this book very hard to read. So much computer language I just couldn't understand. The story is brilliant as is the writing but I just couldn't get involved in this book. Sorry Ellie, first book of yours I'm not giving five stars to but sure others will.
Profile Image for Katie Erickson.
15 reviews
August 31, 2026
love the author, but this book wasn’t the best

This was probably my least favorite book of Ellie masters. I normally love all her books and will keep reading them- however- this one was too confusing with all the cyber terminology. I felt like the main characters lacked depth too- like you didn’t know much about either. I hate rating it only 3/5 but would not read this one again. Writing is always good- just for me not a great storyline.
822 reviews5 followers
Review of advance copy received from Author
August 4, 2026
Hang on to your hat for this one! Julian and Ivy’s story is non stop, page turning action from the first page till the very end. These two find an unbreakable bound on how they see and think their way through anything digital. It’s a wonderful read and the characters of US Marshals: Task Force 9 knows how to deliver!
Profile Image for Carolyn Spence.
2,071 reviews16 followers
August 4, 2026
Nothing like computer jargon to sound sexy from Julian. Ivy is his match in every way and doesn't hold back, she's just not used to having a partner. These men are no nonsense for sure, "Start the coffee." and some sense of humor when required, "budget cuts". This book is full of power moves by each main character. Mesmerizing.
1,401 reviews5 followers
August 5, 2026
I'm so enjoying this new US Marshal series! Julian and Ivy's story was a match made in heaven as they are both computer geeks. I loved how Ivy singlehandedly was able to dismantle an entire corrupt network of bribes and murder for hire plots. A fast past read with two very likeable characters, action, suspense and steam! I'm already looking forward to the next book.
Profile Image for Sherry Wood.
601 reviews5 followers
August 6, 2026
Intense!

Amazing, exciting, intense and fast paced throughout the whole book!! Suspense, tense moments, action, this book has it all!! And a beautiful love story that trust is hard to give but is required. I totally loved this book and definitely recommend reading!! Another awesome masterpiece from Ellie Masters!!!! 5++++ stars!!
Profile Image for Robyn Bagley.
36 reviews
August 10, 2026
This series is scary good!
Good that it has action, great storylines and lots of heat!
Scary as I sure hope nothing like this is actually happening in the world - no I am not so naive to think that is the case. But one can always hope. And if it is I sure hope their are groups like this fighting against it!
Profile Image for Carina Hales.
530 reviews11 followers
August 20, 2026
Wow! This story thrilled from page one and kept the excitement till the very last page.

Ivy and Julian made a perfect pair, they were both brilliant and skilled and connected together beautifully.

The story was intense, so intriguing but fascinating to read, I read this book so fast as i didn’t want to stop!

Overall just a great read and I can’t wait for the next book.
88 reviews
September 8, 2026
I understand

I understood a lot of the computer language in this book because I'm a computer programmer. The average person would not. But I do agree with them on one thing ALL THAT COFFEE Reference WAS Annoying. Give the poor people some food!

A hacker like Ivy and Cipher are a different breed.
1,589 reviews4 followers
August 4, 2026
Wow! This one hits the ground running and is non-stop all the way through! The intensity, the tension between Ivy and Julian is off the charts. This will break your heart, steal it and mend it. NEVER disappointed when I read one of Ellie’s stories!
Profile Image for Anny.
86 reviews
August 7, 2026
Very lethal and absolutely loved it!!!

​A perfect 5-star read! Julian's and Ivy's love story is a lethal worth taking. Ellie Masters ’ storytelling is top-notch as always. I can't wait for the next book in the series!
Profile Image for Amber.
166 reviews
August 8, 2026
This one, like the first one in the series, lacks depth of character development as well as plot. It feels a bit like you got dumped into the deep end. It's intense and fast pace; good enough that I will likely continue reading the series. Hoping the next one is a bit better.
5 reviews1 follower
September 3, 2026
Very attention grabbing

The plot and characters move at a believable pace, keeping the reader's attention and ready for the next test in the story. Different to stop reading once started.
Profile Image for Paula.
2,077 reviews8 followers
September 6, 2026
CIPHER

I absolutely loved this spectacular suspense romance . It's intense , intriguing and definitely a pulse-pounding tale . A well written story . The characters are wonderful . I highly recommend taking the time to read .
Displaying 1 - 30 of 39 reviews