YOU: Lady Phoebe Borehall-Blaxworth

Joe manages to track down Marienne at a London art festival, but she rejects him. A disillusioned assassin hired by the Quinn family, called Elliot Tannenberg, confronts him, but spares him and provides him a false identity in exchange for money. Joe uses his false credentials to become a university English professor. He becomes interested in Kate Galvin, an art gallerist and the girlfriend of his colleague and neighbor Malcolm Harding. After Joe saves Kate from two muggers, Malcolm then invites Joe to a party as a thank you, where he meets aspiring politician Rhys Montrose, artist Simon Soo, and aristocrats Roald Walker-Burton, Connie, Blessing Bosede, Gemma Graham-Greene, and Lady Phoebe Borehall-Blaxworth. After a long night of partying, Joe passes out. The next morning, Joe wakes up at home with Malcolm stabbed to death on his dining table.

After Joe disposes of Malcolm's body, he is sent anonymous texts by Malcolm's real killer thanking Joe for disposing of the evidence. Joe suspects that the killer is one of Kate and Malcolm's friends and infiltrates their social circle in order to investigate them. During the course of the investigation, Simon is murdered while at an art exhibition, Joe's stalker deduces his true identity and Joe forms a sexual relationship with Kate. Joe murders Phoebe's bodyguard Vic.

Phoebe invites Joe along to her Hampshire country house, where he begins to suspect Roald of being the killer and has an altercation with him. After hearing a scream, Joe discovers Kate kneeling over Gemma's corpse with a knife. She pleads her innocence and forces Joe to help her hide the body. Joe is caught by Roald, who attempts to kill him with a rifle, but is quickly incapitated. Rhys arrives and reveals that he is Joe's stalker and the killer.

Chaining Joe and Roald in the catacombs of the country house, Rhys reveals that his plans to murder the rest of the friend group and orders Joe to kill Roald so they can frame him as the killer. When Joe refuses, Rhys sets the catacombs on fire, but Joe and Roald manage to escape. Kate offers to take Joe out on a date, but Joe rejects her, planning to take down Rhys, who announces his mayoral campaign.

Part 2

Back in London, Rhys blackmails Joe into framing someone as the Eat the Rich killer. Joe chooses to frame Dawn Brown, a woman who attempted to kidnap Phoebe. Rhys continues to blackmail Joe and orders him to kill Kate's father, billionaire Tom Lockwood. Officially entering a relationship with Kate, Joe goes to meet Tom, who recognizes him his true identity as Love Quinn's husband and contracts him to assassinate Rhys. Joe learns that Rhys kidnapped and imprisoned Marienne.

Joe tracks down Rhys at his ex-wife's house, unsuccessfully tortures him for Marienne's location and chokes him to death in a rage. When Joe continues to see Rhys, he then realizes that he had developed a split personality that took the physical form of Rhys; the real Rhys had never met him. It was actually Joe himself who kidnapped and imprisoned Marienne and committed the Eat-the-Rich murders.

Rhys Spectre Joe accepts Rhys Joe finds Marienne and resolves to free her after making arrangements to escape. He finds her phone and seemingly realizes that she had lost custody of her daughter, which devastates her when he relays the news to her. He later finds her seemingly dead from overdosing on oxycodone pills he previously planted on her. Believing Marienne to have died, Joe disposes of her body at a park to make her look like she overdosed. His student Nadia Farran, however, plotted with Marienne to fake the latter's death so that she could escape. Luring him with a text from Kate's phone, Joe murders Tom and his bodyguard before preparing to commit suicide out of guilt over Marienne's death and to prevent himself from hurting anyone else. Joe throws himself off a bridge, but his "dark" side survives. Joe accepts that he is a killer for the first time, and, after discovering that Nadia had been spying on him, murders her boyfriend and frames it on her. Kate uses her resources to wipe Joe's past clean and they return to New York. When Joe is looking out the window of their apartment, he sees Rhys staring back at him.