"Adam doesn't need you anymore."
"I could take it. I was stronger than he [Adam] was."
Born in Corpus Christi, Texas, Adam's mother, Rosemary, died when he was five, causing Adam's stepfather, Mark Harrison, who had been abusive towards Rosemary, to begin channeling his aggression towards Adam. Mark would beat Adam, force him to wear girl's clothes, and possibly even molested and sexually assaulted him. To cope with the abuse, Adam developed an alternate female personality that referred to itself as Amanda, and took the abuse for Adam. In and out of the emergency room throughout his childhood, Adam was eventually put into a foster facility in Dallas, and was shunted from home to home. Adam was emancipated at the age of sixteen, and was at some point expelled from school due to bad grades, drug possession, and petty theft. While he was in foster care, Adam met Julie Riley, a university student who volunteered at the foster care facility. Julie befriended Adam, and got him a job and a home at the Hudson Street Hotel at South Padre Island, Texas, when she became manager of it. When Adam was jailed on two occasions, Julie bailed him out, and possibly helped acquire drugs to help counteract his severe migraines. On April 10, 2009, Adam tried to intervene when William Browder made inappropriate advances on another hotel employee, Madison Cooke. When Browder shoved him down, the act provoked the Amanda personality, causing him to tackle Browder into the swimming pool. Along with the enforcement of the drugs he took, the incident drove her, in Adam's body, to kill Browder at the hotel on the next night.
"Adam was special."
"Well if he's so special, why don't you tell me how to find him?"
"Because he's in a better place now."
Adam, as Amanda, is first seen meeting Daniel Keller in an elevator at the hotel, and Daniel takes him to his room, where Amanda kills him. The following morning, Adam, as himself, finds Daniel's corpse inside a closet, which leads to the BAU being called in. After Amanda murders Carl Cade at a different hotel, the BAU deduces that the unsub could be one of the employees at Hudson Street. Adam is initially interviewed by Reid and Morgan. He does appear to fit the profile the team puts together, as he is a submissive male. The team theorizes that the unsub is actually a killing team, comprising of a dominant male and a submissive female. It is thought that the female lured the young men into the hotel rooms, tied them up (with consent), then the male would rape them and kill them. The team, being prompted by info from Garcia, begin to suspect Julie and Adam as the killers, but with roles reversed; Adam was the submissive. After the two of them pass a polygraph, Reid realizes that Adam suffers from a split personality. He comes to this conclusion after Adam stares him down confidently upon his release; an uncharacteristic act for a submissive.
Julie searches for Adam later on in his hotel room and finds several items belonging to the previous victims. She confronts him, but his female alter-ego takes over again, waylays her, and escapes. The team now knows that Adam is the sole killer and his female side is dominant and confident; a definite, stark contrast to Adam's personality. Adam, in the Amanda personality, travels to nearby Corpus Christi to find her stepfather. The team confronts Adam as she holds her stepfather at knifepoint and tied up with a plastic bag over his face. Reid, who wants Adam alive, talks her into allowing Morgan to arrest her, but beforehand, the Amanda personality, in an act to protect Adam from the consequences of her actions, apparently takes permanent possession of his body, much to Reid's dismay. Amanda, clothed in full wig and makeup, is then interviewed by Reid in a mental institution and tells him that he will be waiting for a long time to see Adam return (although she doesn't look at him confidently, implying that Adam is already in control). Reid, who had a past encounter with a serial killer named Tobias Hankel who had suffered from the exact same condition that Adam had, believes that Adam can be saved, if only he could reach him.
"My name...is Amanda."
The unsub was initially profiled to be a two-person killing team comprised of one man and one woman, both in their twenties. The man would probably be a heterosexual who is very submissive in his everyday life and with everyone except for his partner, to whom he becomes dominant with. The female would probably be socially awkward, of average intelligence, emotionally unstable, reclusive, has a problem with authority, and can't interact with dominant personalities. At least one of them is either a guest or an employee of the Hudson Street Hotel. Raping the victims is about having power and dominance over them, not sexual orientation. When Julie Riley was declared a suspect, the profile changed the roles of the killing team according to gender. However, it is revealed that there is only one unsub, who is suffering from dissociative identity disorder due to numerous childhood abuses: his default personality is submissive and meek; his dominant personality is confident, violent, and vengeful. The dominant personality chooses victims that heavily resembled someone in the submissive personality's life: abusive alpha males who feel that women are their property. The unsub is highly intelligent and was able to slightly thwart the team's investigation by changing venues and passing a polygraph test.
It is obvious to Rossi, however, that the unsub, when in his default personality, has no idea what he does when the dominant personality takes over. This is the reason why Adam was able to pass the polygraph test.
The Amanda personality targeted Caucasian college students with alpha male personalities and aged in their early 20s, all of whom were surrogates for Adam's abusive stepfather. She would lure them into a hotel room where, while dressed like a woman in Adam's body, she would convince them to let her tie their arms and legs to the corners of the bed. She would then rape them (presumably as a reference to the alleged sexual abuse Adam suffered at the hands of his stepfather) and then fatally suffocate them with a plastic bag. She would then pose the bodies in fetal-like positions and stuffed them inside the closets to make the maids believe that the rooms were vacant so they would be cleaned, since the maids never check the closets.
Her first two victims were killed at the Hudson Street Hotel, where Adam worked at, but after the BAU turned up to assist the investigation, the third victim, Carl Cade, was lured to and killed inside a different hotel to prevent herself from being spotted. When she tried to kill Julie Riley, she threw her off the roof of the Hudson Street Hotel. In the case of Mark Harrison, Adam's stepfather, she presumably forced him into his bedroom at knifepoint, where she then tried to kill him by suffocating him with a plastic bag.
Adam's background seems to be loosely based on that of Henry Lee Lucas and Daniel Camargo in the sense that all three were abused by their parents as children (Lucas by his mother, Camargo by his stepmother, Adam by his stepfather), which included dressing them up in girls' clothing. He also seems to be based on Billy Milligan, who also had multiple personalities, one of which was a woman who raped three other women. Adam is also similar to both John Wayne Gacy and Robert Berdella. All three were abused by their fathers (Gacy and Berdella were abused by their fathers; Adam was abused by his stepfather) and targeted the same type of victims (teenage boys and young men), whom they would lure, rape, and kill by asphyxiation. Also, the scenario of Adam's split personality committing his murders is an allusion to Gacy's claim that he had a split personality who was responsible for killing his victims.
- 2009, Texas:
- South Padre Island:
- April 11: William Browder
- April 13: Daniel Keller
- April 14: Carl Cade (killed at a different hotel)
- April 16:
- South Padre Island: Julie Riley (his boss; attempted, but barely survived; threw her off a roof)
- Corpus Christi: Mark Harrison (his stepfather; attempted, but survived; was non-fatally suffocated and held at knifepoint)
- South Padre Island:
- Adam is similar to Season Two serial killer Tobias Hankel, who was also abused by his father as a child and had a split personality that would kill his victims for him. Reid also became personally involved in both of their cases.
- In a deleted scene of the episode, Adam shoots Morgan in the shoulder. This scene, excised for unknown reasons, can be seen in the Special Features on the Season Four DVD release.