A man with a bludgeoned head exits a cab and limps towards an FBI Field Office to hand himself over into police custody, grabbing attention of nearby bystanders as dollar bills fall out of his hands. The building's security guard walks over to arrest him, demanding he raises his hands. Paul obliges, removing the blood-stained cloth to reveal his facial injury as his still functioning right eye dangles from the socket.
At a hospital, upon receiving medical attention, Paul is questioned by an agent after claiming responsibility for one count of arson and kidnapping, each, and at least fourteen murders. The man questions the authenticity of his statement noting that there isn't any evidence for this, to which Paul replies "Of course not... That's my job".
At Murkoff's Rehabilitation Center, Pauline Glick is questioned by two Murkoff agents about Paul Marion, her former partner's whereabouts in attempt to minimize any caused and prevent further damage to the company. Not knowing when Marion turned against them, the agent asks for Glick to "start at the beginning". Pauline recalls their investigations behind The Hat Box Murders, later revealing that all three victims were Iraqi veterans from Spindletop Psychotherapy Clinic, a hospital owned by one of Murkoff's branches.
At the clinic, The Pauls meet up with Chief Psychiatrist Doctor Claymore, who was not under Murkoff's direct management, leaving Pauline to attempt to persuade him into cooperating by providing confidential information regarding experimental dream therapy conducted on their patients and altering his FBI testimony. Upon explaining their roles as mitigation officers, Claymore refuses to comply without a warrant.
Instead, he provides a brief summary of their results, which, initially proving successful, ended up exacerbating patients' psychological traumas. After being stonewalled by the Doctor, the two head over to Murkoff's building surveillance, where a security guard, Chris "Strongfat" Walker, explains that none of their personnel know that they're being monitored. Walker plays back the last therapy sessions from the three known victims: Martin Bellmont, Priscilla Clarke and John Bowers, each speaking indecisive sentences. Paul asks Walker if any violent outbursts occur, as he pulls up a recording of Omar Abdul Malik which shows him attacking Claymore during one of their sessions. Pauline asks for audio copies and the Pauls go looking for the veterans' widows, tricking them into signing arbitration agreements in order to avoid million dollar lawsuits. While Pauline handles the paperwork, Paul notices the widow's daughter drawing a family picture in which her father's represented as a blood-stained Apkallu, ancient Mesopotamian demigods whose sculptures were propped in Claymore's office.
Back at Spindletop, the Pauls discover Doctor Claymore's decapitated corpse in a trashed office and the destroyed surveillance system. As the killer's motivation was the culmination of all sessions, the two conclude that the perpetrator is Chris Walker, as he was the only other person who heard everything the patients said.
They break into Walker's house and find four separate coolers, each of them stuffed with a head from one of the three victims and an empty one reserved for Claymore. Pauline calls for a security team while Paul explores Strongfat's bedside, finding a stuffed animal from his childhood next to the family photo, as Walker peers through the door frame, carrying Claymore's head in a blood-soaked bag. Pauline pulls a gun holstered around her ankle and orders him to stand down, as Walker bursts in rage, throwing her across the room and picking up Marion by the neck. Glick recovers and lands a shot through his jawline. This only infuriates Walker, as he knocks her through a window before Marion manages to get to his gun and fires off two rounds. Chris, still standing, slams Paul to the ground, exclaiming "little pig", but before he can get to him, Pauline starts up the car and crashes into the crazed man. She reports back and the two clean up the crime scene, as Paul makes a remark that Walker has just retired.
Following the incident, Walker is sent to Mount Massive Asylum and all four heads are transferred over to Omar's apartment, framing him for the Hat Box Murders. Marion notes that Malik's "name and skin color did the heavy lifting". Seeing Marion's mortification, the Agent asks for his motivations behind the work, as Paul reveals that Murkoff's pharmaceuticals and gene therapies offered an experimental treatment to save his daughter from a rare blood disease that killed his wife.
In present day, Pauline concludes to Murkoff agents that Paul never found out how far they went with their research at the asylum, almost feeling sad that he, at the time, still thought they were partners instead of Marion being her target.
List of characters in order of appearance:
- Paul Marion
- Pauline Glick
- Omar Abdul Malik
- Doctor Claymore
- Chris Walker
- Martin Bellmont
- Priscilla Clarke
- John Bowers
- Alice Marion