The novel opens under cover of darkness as unidentified men use a backhoe to bury a large man named Keever in a hog pen near an isolated farmhouse, choosing the location because the hogs' constant disturbance will mask any evidence visible from the air.
Jack Reacher, a former U.S. Army Military Police major who drifts across America with no home or possessions, steps off a late-running evening train at a tiny depot called Mother's Rest, drawn solely by the town's evocative name. A woman emerges from the shadows expecting someone else: Michelle Chang, a former Federal Bureau of Investigation (FBI) agent turned private investigator, waiting for her colleague Keever. Keever called Chang to Mother's Rest for back-up on an off-the-books case but has failed to appear. The one-eyed motel clerk gives them rooms, then phones someone to report that Chang met a man off the train.
Reacher finds no museum or memorial explaining the town's name. Instead, he notices organized surveillance: a boy tails him, a spare-parts clerk reaches for the phone upon seeing him, and all sightings funnel to the town's leadership through the motel clerk. That evening, Reacher watches the spare-parts clerk greet a gaunt man in a suit arriving by train with a deferential handshake, confirming some organized operation. They search Keever's motel room and find belongings but no notes. Behind the bathroom trash can, Reacher discovers a scrap of memo paper bearing a Los Angeles phone number and the words "200 deaths."
Two men named Moynahan, nephews of the motel clerk, follow Reacher and Chang on the road toward Oklahoma City, trying to force them to return the room key. Reacher disarms both and takes their weapons. At Keever's house, the home office has been stripped of all paper while cabinets still hold blank supplies, proving someone used Keever's keys to remove his files. Reacher concludes Keever is a prisoner. On the nightstand lies a
Los Angeles Times magazine open to a partially read article by Ashley Westwood, the paper's science editor, bookmarked at its start. A second bookmark bears the same phone number and a notation linking Mother's Rest to the name Maloney.
They return to Mother's Rest, where the clerk apologizes and grants access to room 215; Reacher surmises the leadership ordered calm for an important visitor. A woman in white departs another room via an unmarked white Cadillac. When roughly 30 local men surround their car, Reacher warns them about the tactical futility of their confrontation and refuses to yield. The standoff dissolves when a pragmatist loads their luggage.
Chang reaches Westwood by phone; Keever never contacted him. Reacher theorizes that Keever's client had been calling Westwood directly until blocked, then re-approached under the alias "Maloney." In Los Angeles, they search Westwood's call records and trace the most likely candidate to a shared phone at the Lincoln Park branch of the Chicago public library, registered to "McCann." Chang's phone company source confirms the Maloney cell was a burner sold next door to that library, establishing McCann and Maloney as the same person.
The operation's leader, a man with blow-dried hair based 20 miles south of Mother's Rest, has hired outside security through a Ukrainian crime boss named Merchenko. A surveillance operative named Hackett, tracking Chang's phone, attempts a drive-by shooting on the 405 freeway but loses them after a collision. Reacher glimpses the shooter and recognizes him.
In Chicago, library volunteers describe Peter McCann as an older, unhappy man who has not been seen in weeks. His apartment is unlocked, filled with 15 computers and technical books, but McCann is gone. Hackett appears at the door with a silenced pistol. Reacher disarms and subdues him. The pistol is one round short: Hackett shot and killed McCann before coming for them. McCann's neighbor, Mrs. Eleanor Hopkins, a retired researcher, explains that McCann was obsessed with the Deep Web, the hidden portion of the internet invisible to standard search engines. She mentions that McCann has a sister, Lydia Lair, near Phoenix, Arizona.
Using Hackett's phone, Reacher delivers a threatening message to Merchenko's organization. In Phoenix, Lydia reveals that McCann's son Michael has a condition she describes as having his happiness meter permanently stuck on zero; Westwood later identifies this as anhedonia, the complete inability to experience pleasure. Michael went missing after visiting a friend near Tulsa, Oklahoma. McCann traced Michael's phone from Tulsa by bus, then northward by train, but the signal died north of Oklahoma City and never reappeared. McCann believed Michael got off at Mother's Rest and hired Keever to investigate.
Three of Merchenko's men invade the Lair home, threatening violence against Lydia's daughter Emily and Chang to learn who has been talking to Lydia. Reacher retrieves a revolver from the bedroom and shoots all three; two die immediately. Reacher later kills the wounded third man in a coffee shop by compressing his carotid arteries, an act Chang protests before reluctantly accepting his reasoning. They then locate Merchenko behind his strip club near the Phoenix airport, and Reacher shoots him.
Westwood shows them satellite images of a farm south of Mother's Rest. In San Francisco, a coder demonstrates Bathyscaphe, his Deep Web search engine, and locates Michael McCann's posts on suicide-related boards. Michael, posting as "Mike," connected with a suicide partner called "Exit." Another user recommended "MR," short for Mother's Rest, as a reliable source of Nembutal, a barbiturate considered ideal for painless suicide. The Mother's Rest website offers mail-order Nembutal and a premium "concierge service": Clients travel by train, stay at the motel, and are driven to the farm for assisted death. Examining satellite photos, Reacher notices no exhaust pipe connects any outbuilding to the supposed suicide suite, proving the site is partly fabricated.
In Oklahoma City, the three plan their assault. Westwood enters Mother's Rest posing as a suicidal client requesting the concierge service. Reacher and Chang infiltrate the town in a FedEx truck, timed with the morning train and rented helicopters as diversions. They subdue conspirators one by one. The remaining four men flee to the farm. Reacher, Chang, and Westwood pursue in a commandeered backhoe through wheat fields to avoid the potentially trapped road. A firefight erupts, and Reacher kills the diner counterman and the one-eyed clerk.
Inside the "suicide suite," they discover the true operation: a white-tiled torture and murder studio equipped with cameras, microphones, professional lighting, and restraints. The woman in white from the motel is chained dead to the wall. A printed e-mail reveals a custom murder order with the client willing to pay $100,000. The farmhouse computers contain over 200 pay-per-view snuff films spanning five years, streamed to Deep Web customers who pay for murders performed to specification. Chang identifies one video as almost certainly depicting Michael and his partner Exit. Reacher and Chang kill the hog farmer inside the studio, then pursue the blow-dried leader outside. Chang shoots him, declaring it is for Keever. Reacher dumps the body over the hog pen fence.
A teenage girl at the motel reveals that "Mother's Rest" is a corruption of an old Arapaho word meaning "the place where bad things grow," a fact local farmers have long suppressed. Westwood stays to document the story. Reacher asks Chang to come with him. She tells him she will not answer that question in Mother's Rest and instructs him to get in the car. They drive west together.