Stilwell visits Avalon Hardware, where the owner, Ned Browning, confirms that he’s missing spray-paint cans matching the colors used in the graffiti, which he believes were shoplifted. Stilwell then goes to Avalon High, which serves as the K-12 school for the whole island, and speaks with security officer Olester Bryant. Bryant identifies “FSID” as standing for “Free speech is dead” (198), the name of an unsanctioned student club. When shown a photo of the tagger from the security video, Bryant identifies him as Matthew Allen, the son of Mayor Douglas Allen, whom Stilwell had previously arrested on corruption charges. Since the mayor’s trial is imminent and Stilwell is prohibited from contacting him, he can’t go to the Allen home. To avoid the appearance of a vendetta, Stilwell arranges for Bryant to bring Matthew to his office the next morning for an informal discussion rather than an arrest.

The next morning, Bryant brings Matthew to meet with Stilwell. Matthew is wearing a hoodie with a blue paint smear on the sleeve. During the recorded conversation, Matthew admits his involvement with the FSID group. He expresses contempt for his father but accuses Stilwell of targeting him to hurt his family. Stilwell offers to drop the matter if Matthew promises to stop the vandalism. Matthew reluctantly agrees.

Stilwell takes the ferry to the mainland, where he encounters Kent Middleton, who claims that he’s traveling for a job interview with the state parks service. To maintain his cover, Stilwell sits with him. He then sees Laffont and Masser nearby, realizing he has stumbled into their surveillance operation. In the restroom, Stilwell and Laffont argue about the compromised surveillance, with Stilwell noting that Laffont should have told him when Middleton left home. Middleton enters, Laffont leaves, and Middleton tells Stilwell that the two men who just moved into Bird Park want to buy the ABC vineyard.

Detective Ballard calls Stilwell to apologize for the lack of communication regarding the Middleton surveillance. Stilwell then visits Deputy Ramirez. Unable to speak, Ramirez communicates with a digital tablet. She reveals to Stilwell that the shooter yelled Quigley’s name before opening fire. Ramirez also confides that she and Quigley had been in a secret relationship for five weeks. She relays that Quigley claimed that his wife had cheated on him, though Stilwell doubts it, reasoning that Quigley was more likely to have been unfaithful. Ramirez tells Stilwell that Quigley’s divorce attorney was a former police officer named Benito Martinez, who also handled Stilwell’s divorce before he moved to Catalina.

Stilwell goes to the Long Beach Courthouse and confirms from public records that Quigley had initiated divorce proceedings before he transferred to Catalina. He then visits the attorney, Martinez, who initially refuses to violate attorney-client privilege, stating that he already denied the same request from Detectives Simon and Trestle. Stilwell presses him. While maintaining his official refusal, Martinez provides an important clue, saying he left Quigley’s funeral because of the hypocrisy of one of the speakers. From this hint, Stilwell deduces that Lieutenant Lambert was having an affair with Quigley’s wife, which would have been exposed in the divorce. Stilwell receives an urgent call from Ballard, who informs him that Middleton is actively stalking someone.

Stilwell joins a briefing at the LAPD Open-Unsolved Unit with Ballard’s team and the Special Investigation Section (SIS). After Middleton’s job interview, Ballard’s team sent him a “Trojan horse” email that installed keystroke-logging software on his computer. They discovered him cyberstalking Molly Young, a hiking guide. Middleton has booked a private hike with Young under two false identities, one male and one female, to try to work around her two-person-minimum safety rule. The SIS will conduct surveillance along the trail. After a debate, they decide not to warn Young, making her an unknowing participant, or “pigeon.” Masser explains that an overt act, which can be as little as looking around to check for witnesses, is needed before arrest and that important evidence such as a shovel and bindings is likely in Middleton’s backpack.

From a mobile command post, Stilwell and Ballard’s team watch the surveillance feed from the trailhead. Young is about to cancel the hike because her clients are late, but Middleton arrives just in time. He introduces himself with an alias, and Young explains that the second hiker is a no-show. Young tells him that she must cancel due to her safety protocol of never hiking one-on-one, and Middleton tries to convince her to hike anyway. When she mentions the recent discovery of a dead hiker on Catalina, Middleton frightens her by saying that he was there before explaining that he was called to the scene as a ranger. He then unzips his backpack and reaches inside while Young has her back turned. Seeing this as a potential imminent threat, Ballard orders the SIS team to move in. They swarm the parking lot and arrest Middleton. However, an inventory of his backpack reveals no evidence of any plan to hurt Young. The murder kit is gone.

Stilwell, Ballard, and Laffont arrive at the scene to find that SIS searched Middleton’s rental car without a warrant and found nothing. Masser reports that they have no evidence to hold him. Stilwell locks eyes with Middleton, who’s handcuffed in a police car and gives him a smug smile. After a brief argument between Stilwell and Laffont over who blew their cover, Stilwell insists that they hold Middleton for 48 hours. Masser devises a plan to arrest him for attempted abduction based on his use of false pretenses, giving them a window to find the real evidence. Stilwell reasons that Middleton dumped his murder kit after realizing that he was under surveillance. The only unsupervised moments were inside the Reagan State Building during Middleton’s interview and when Middleton used the restroom, leading Stilwell to conclude that the evidence must be hidden in the restroom.

At the Reagan State Building, Ballard’s team splits up to search. Laffont and Stilwell check the fourth-floor men’s restroom, including the drop ceiling above the toilet stalls, but find nothing. Meanwhile, Ballard and Masser search the state parks office and learn from Middleton’s interviewer that he was never left alone. As the defeated team rides the elevator down, Stilwell realizes that Middleton rode the elevator by himself. The group looks up in unison at the elevator’s emergency escape panel, immediately understanding where he must have hidden the murder kit.

In an interview room, Stilwell and Ballard confront Middleton, who believes they have no evidence. After reading him his rights, Stilwell places a box on the table and removes a spiral-bound notebook. For a moment, Middleton’s arrogance vanishes, replaced by a “game-over look” before he regains his composure (253). Ballard reveals that the notebook, found hidden in the elevator, contains maps and descriptions of his kills, including a fifth, previously unidentified victim. Stilwell lays out the rest of the murder kit, including gloves matching those used by the conservancy, duct tape, a rubber-banded coil of snap ties, a hood, a garrote, and a folding shovel. Middleton lunges at Ballard but is stopped short by his handcuffs, smashing his face on the table. Bleeding from a broken nose, he demands a lawyer. As they leave, Ballard taunts Middleton by saying that a woman defeated him, and Stilwell stares at Middleton, who curses at him.

Ballard, Laffont, and Stilwell discuss preparations for prosecuting Middleton, and Ballard asks Stilwell to seal Gwen Bassett’s apartment and secure housing for her. Ballard walks Stilwell to his car and tells him that, though she told Middleton he was defeated by a woman, she wants to give Stilwell credit for solving the case. Stilwell offers to let Ballard take credit to get more resources for her department, and she says “goodbye” in Hawaiian.

Stilwell returns home late to Catalina after dealing with Bassett and sealing her apartment as a crime scene. He finds Tash watching a comfort movie. He tells her that they have arrested Bassett’s boyfriend for the murder of the hiker. When he says he must keep the details quiet, he inadvertently hurts Tash’s feelings by implying that she’s Lionel McKey’s source for police updates. He apologizes, blaming his exhaustion. After a shower, he finds Tash asleep. He’s relieved for the quiet, as his mind is already shifting from the now-solved Middleton case to the dangerous, unresolved threat posed by Lieutenant Lambert.