‘Chain Reaction’ Review: When Jack Reacher Takes on Artificial Intelligence, There's Only One Winner
For nearly 30 years, Jack Reacher has traveled around America, trying to stay out of trouble. But trouble always seems to find him. Like a huge elephant with the brain of Sherlock Holmes, he uses his fists to deliver justice when needed. However, the world has changed since Lee Child first introduced the former military policeman in Killing Floor. Keeping a traditional wanderer like Reacher interesting in a world that depends more and more on digital technology is an interesting challenge.
In Chain Reaction, the 31st book in the bestselling thriller series, Andrew Child takes full control of Reacher's adventures for the first time. He brings back a familiar character and puts Reacher in the middle of a plot involving artificial intelligence, corporate spying, and modern surveillance. With a new author in charge and technology threatening Reacher's old-fashioned way of life, does Jack Reacher still belong in the modern world? Can he keep doing what he does best without losing what makes him special?
‘Chain Reaction’ Remembers That Reacher Is a Detective
The story brings Susan Turner back into Reacher's life. She has now been promoted to general and leads the highly secretive G-99 Section. One of her investigators has been murdered while working on a case in Colorado. Several things about his death do not make sense, leading Turner to believe it was not the random crime it first appeared to be. She also does not know whom inside her own organization she can trust.
Very few people can find Reacher because he chooses to stay out of sight. Turner is one of the few who knows exactly how to reach him. Soon, he is traveling across the country at the government's expense. This is a rare luxury for a man who usually takes Greyhound buses and stays at whatever motel has a room available. Meanwhile, the murder investigation grows into something much bigger.
This is classic Reacher, a kind of homeless Sherlock Holmes. It is easy to focus on his huge body and his ability to smash someone's knee into pieces, especially after the TV series made his size impossible to ignore through Alan Ritchson. But the best Reacher books have always shown that his brain matters just as much as his body. He is an excellent detective who just happens to be as big as a rhinoceros. Thankfully, Chain Reaction understands this.
Reacher notices things other people miss. For example, he spots when a car seat is set at the wrong height for the person who supposedly drives the car. He also notices when an ordinary-looking object is not quite what it should be. Something about the scene does not feel right. None of these clues solves the case by itself, but Reacher remembers them until details that seemed unrelated begin to fit together.
This shows how satisfying it can be to watch Reacher use his brain when faced with the enormous power of artificial intelligence. In one great moment, he confuses AI by asking very simple questions. He knows he cannot beat a computer at processing huge amounts of data, so he does not try. Instead, he asks the kind of question a machine may not know how to answer: What am I actually looking at?
One of the book's smartest ideas is that problems that seem digital can sometimes be solved by looking at the real world. Artificial intelligence can only know what it has access to. It cannot see everything, and having a huge amount of information does not always mean understanding what is happening right in front of you. Thankfully, Reacher is very good at looking closely.
Susan Turner Is the Perfect Mirror for Jack Reacher
Bringing Turner back gives Chain Reaction more emotional depth than another short-lived partnership with Reacher would. She is not just a familiar face from the past. She is a reflection of Reacher: the general he might have become if he had stayed in the military. They respect each other because they know they are equals, even if the official records do not say so. But the relationship works both ways. Turner has earned promotions, taken on more responsibilities, and learned modern military procedures that Reacher no longer knows. Reacher understands this.
One of Reacher's most appealing qualities is that he is never embarrassed to admit what he does not know. If someone else knows more about something, he listens. Turner understands the military world he is stepping back into better than he does, so he is happy to rely on her knowledge. Their romance works for the same reason. Both know that every time they are together could be the last. Turner is wise enough to know she will not persuade Reacher to settle down. Reacher does not insult her by pretending that he might. Readers would not want him to change that part of himself, either. Jack Reacher's appeal depends on one thing: in the end, he walks away.
Give him a mortgage, a Wi-Fi password, and a Costco membership, and you would destroy him more effectively than the hundreds of people who have tried to kill him over the years. Turner may get closer to him than most people, but even she knows that loving Reacher and keeping him are two very different things. This does not mean he has no feelings. In fact, some of Chain Reaction's best moments show his gentle side, especially when he meets a baby caught up in the events of the investigation.
Reacher would never choose to become a father, but he knows how to hold a baby and understands that he must protect a child who needs help. These moments make him feel especially human. Although Reacher is a lone wanderer, he still enjoys having someone beside him in bed, cares deeply about the people who have earned his loyalty, and fights for what he believes is right. His idea of honor simply does not require him to fight fairly.
Andrew Child Lets Reacher Talk Again
Making Reacher feel more human is another sign that Andrew Child has brought some of his own style to the writing. In this book, Reacher talks more than he does in some of the later novels, where his replies became shorter and shorter. Child has said he wanted to bring back the more talkative Reacher from the earlier books. Indeed, Lee Child has also talked about how quiet and gruff Reacher had become. Reacher uses words to throw his opponents off balance, too. Sometimes he provokes them because angry men are easier to predict. Other times, he simply makes a joke. Despite everything, Reacher has always had a sense of humor.
Reacher fights dirty. He cheats whenever he gets the chance and has no interest in giving his opponents a fair fight. But Chain Reaction keeps the funny, detailed descriptions of how his fights work. Weight, movement, angles, and body parts all matter. As the series says, details matter. A knee does not simply get hurt because Reacher kicks it. The book explains enough for readers to understand why the joint is about to stop working. Of course, this is ridiculous, but that is part of the fun. It has always been part of the fun of reading Reacher. The book still tells us every little detail about what he eats for breakfast, but a night with Turner can be described in just one sentence. He knows what matters to him.
Most importantly, Reacher's sense of right and wrong stays much the same. He does not care about following rules made by people he considers worse than himself. What matters to him is why someone uses violence and who benefits in the end. This has always allowed the series to feature an extremely violent hero without making him a bully.
‘Chain Reaction’s Climax Is Over a Little Too Quickly
If there is one area where Chain Reaction falls short of the very best Reacher books, it is how quickly part of the ending is resolved. The investigation builds slowly and carefully, grows bigger, and takes Reacher to different places. Traveling helps the story a lot. The action never feels stuck in one place, and the book is short enough that the investigation does not drag. That is why one of the final confrontations feels a little too short, though not completely rushed. The story sets up a serious threat and puts all the pieces in place, but then deals with the problem faster than expected.
On the positive side, the ending works much better because, without giving away spoilers, Reacher and Turner can enjoy themselves once they have dealt with the hired fighters. The main villains turn out to be greedy people who think they are smarter than everyone else, and that is exactly how it should be. Not every Reacher villain needs an underground hideout and a plan to take over the world.
Sometimes people do terrible things because they want a huge amount of money and do not want anyone to stop them from getting it. Once their hired protection is gone, there is no reason for them to suddenly become fighters who can match Reacher and Turner. Thankfully, the punishment they receive is just as harsh and precise as readers would hope, because Reacher does not like it when the balance of justice is wrong.
Andrew Child Has Jack Reacher Figured Out
Chain Reaction ranks somewhere in the middle of the Reacher series. It does not quite reach the level of Tripwire, One Shot, Echo Burning, or Worth Dying For, but those books set a very high standard. Other readers will, of course, have their own favorites. It is hard to find a Reacher novel that is not enjoyable in some way. Based on the series' steady quality over many years, an 8-out-of-10 Reacher book is almost exactly what readers have come to expect. More importantly, this is Andrew Child's first solo book featuring the character.
Readers naturally wondered whether a Reacher novel would still feel like Reacher once Lee Child was no longer writing it himself. This book gives a reassuring answer. Andrew is clearly not trying to change the character just to prove that he can make him his own. Instead, he understands which parts can change and which must stay the same. The world can change, technology can change, and new threats can appear. Reacher can even become a little more comfortable using modern technology. But he is still Reacher.
Reacher will always be funny and observant, caring and extremely violent. He is still willing to cross the country at a moment's notice when someone he trusts says something is wrong. And he is still happy to find a practical, real-world answer in a digital world. This is not Andrew Child's version of Reacher, nor is it a copy of Lee Child's Reacher. It is simply Jack Reacher. It is Reacher. And when Reacher takes on artificial intelligence, there was always going to be only one winner.
Chain Reaction releases on October 20.
Chain Reaction
- Author
- Lee Child and Andrew Child
- Genre
- Thriller
- Publication Date
- November 3, 2026
- Publisher
- Penguin Random House
- Reacher gets to talk more.
- Reacher is updated to fit a more modern world.
- Turner's return is welcome, and she makes a good contrast to Reacher.
- The ending feels a little rushed.