"I promised I would always take care of you, and I meant it. I would never leave you again."
Eddie was born in Chicago, Illinois, in or around 1972. His mother died from childbirth, leaving him to be raised by his father, Edward Wilcox, Sr. In 1977, when Eddie was five years old, his father drove them both to Los Angeles, California, where a job opportunity had opened up for him. However, that same year, the job fell through, and the elder Wilcox, distraught from this, committed suicide by shooting himself on February 2, leaving behind a suicide note written on a stack of postcards. The authorities discovered his body two days later after an L.A. County postman reported an odd smell coming from the house. Eddie was found sitting next to the corpse, having been sitting there ever since his father shot himself. His father's suicide would go on to leave a permanent imprint on Eddie's mind since then. For the rest of his childhood, he had been in and out of jail for several offenses. During his adulthood, he married a woman named Melody Grimes and had a daughter, named Samantha, with her; their marriage was an unhappy one. Becoming a robber and a car thief (the latter skill of which being acquired from his abilities as a mechanic), Eddie used the money from his heists to support his family, but Melody became suspicious.
Eddie was later arrested for his car thefts, and Melody divorced him, relocating to Wichita, Kansas, with Samantha. The latter soon came into constant contact with her father afterward, in which she would complain about her life and express her desire to leave Wichita. On October 22, 2013, he and a partner named Christopher Corbone, who had been briefly incarcerated in the same prison as he was, committed a robbery at a pawn shop, and Corbone unexpectedly shot and killed the store owner and the customer present before they stole $25,000 worth of cash and jewelry. Horrified by the killings, Eddie argued with Corbone, who then tried to kill him when he turned his back on him, but his gun jammed; Eddie promptly fired back, killing him, but he continued to shoot Corbone's body in panic before fleeing. When the store robbery and killings broke the news, Corbone's murders of the owner and the customer were also pinned on Eddie. Since Corbone had connections with the Riggio family, a Mafia organization active in Chicago, Eddie decided to spend one last time with Samantha before committing suicide, knowing that he was a nobody who would only bring more trouble for his family.
Tracking Samantha and Melody down at Wichita on the day following the pawn shop robbery, Eddie waits until Samantha sneaks out of the house to see her boyfriend, Tommy Burns. The two of them go to a secluded area and kiss in his car, but Samantha tries to break away when Tommy tries to have sex with her. When she slaps him, he is infuriated and tries to attack her, but Eddie immediately ambushes them, pulling Tommy out of the car and beating him into unconsciousness before trying to bludgeon him with a crowbar. However, he relents when Samantha yells at him. He then takes her, telling her that he received a job in Mexico and that they would be going there. The attack on Tommy and Samantha's subsequent disappearance was initially assumed by local authorities to be a classic parental abduction, which led to the BAU being called in due to his violent tendencies. Driving into Texas, Eddie wakes Samantha up and gives her a granola bar. He then pulls over alongside a highway and apologizes to Samantha for attacking Tommy.
Later, as they drive down the highway, Samantha suggests likely locations that they can visit while looking at a map before Eddie spots a police officer. He pulls out his handgun in preparation, and the police car flashes its lights, but it races past their car. Samantha then asks Eddie if he was planning to shoot the police officer inside, and he denies it, saying that he would've checked the glove compartment where the gun is contained. The two later arrive in Amarillo, where a gas station owner spots Eddie and recognizes him from the news. Eddie notices the owner calling police, and tells Samantha to go and buy him something when she decides to go back to a motel they are staying at and take a shower. When she leaves, Eddie cuts out the telephone line and then enters the convenience store. He purchases a bag of potato chips, a pack of gum, and six postcards as the owner, operating the register, subtly reaches for his shotgun. However, Eddie is faster, and he shoots the owner twice, killing him before leaving the store, carrying the items with him. He then sneaks into a car yard and steals one of the cars, as well as a big-rig communication radio.
Eddie then drives back to the motel, where he is confronted by Samantha, who has seen the news, which states that he is being suspected of the pawn shop robbery and killings. When she asks him if he killed those people, he angrily denies it, promising that he will tell her what happened when she gets into the car, and then orders Samantha to change into her clothes. In the car, Eddie tells her about what Corbone did, but doesn't specifically tell her that he murdered anyone. Later, the two arrive in El Paso, where Eddie tries to steal another car, but is attacked by the owner, who shoves him to the ground and begins kicking him. Angrily, he takes out his gun and shoots the man in the stomach, killing him in front of Samantha. Shocked, Eddie tells Samantha to get into the car and drive it, which she fearfully does. The following night, he comforts Samantha, saying that had he not killed the man, he would be dead and she would be halfway home. He then says that he promised he would always take care of her and that he would never leave her again.
The next morning, a sleep-deprived Eddie drives into Los Angeles, California, where his father committed suicide. There, he wakes Samantha up and introduces her to the beach. Then, a police officer drives up behind them and flashes its sirens, quickly followed by more cruisers. Feeling cornered, Eddie drives up to a store tent and orders Samantha to get out. When she does, he does so as well and holds her at gunpoint, threatening to police officers that he will shoot her. The two then take refuge inside the tent, where a terrified Samantha yells at him for making those threats. The BAU arrive, and JJ calls him through a nearby telephone, telling him about her sister Rosaline, who committed suicide. She then tells him to release Samantha and give himself up for her sake. However, Eddie refuses and starts smashing the telephone. He then releases Samantha, but she runs back to him and pleads with him to surrender, reminding him about the promise he made to her and also promising to him that she will write postcards to him. At first, it appears that Eddie orders her to leave, as she emerges from the tent alone, but Eddie then follows behind her. The two hug before being pried away by two SWAT agents, much to Samantha's dismay.
Eddie is armed, dangerous, smart, criminally sophisticated, and knows police procedure as well as how to use it to his advantage. He may be out of cash from the robbery, but his need to keep a low profile means that he will resort to his robbery skills at some point. Eddie is also a skilled car thief, meaning he will switch vehicles often, and he has evolved into a sociopathic spree killer with the ego of a career criminal, so there is no telling how far he will go to save himself. This aforementioned ego may be feeding a pipe dream, possibly in which, if he escapes, he can have a healthy relationship with his daughter, whom he believes was taken from him. When reality sets in and the dream shatters, Samantha will be in the greatest danger, since the majority of cases like Eddie's end in murder-suicide or suicide by cop. He is likely sleep-deprived and irrational, and will become more dangerous the closer law enforcement gets.
During his killing spree, Eddie shot his victims with a .45-caliber Kimber Warrior handgun. He also assaulted Tommy Burns, Samantha's boyfriend, breaking his jaw and giving him a concussion, before trying to bludgeon him with a crowbar, but relented. All of the victims were killed either out of self-defense or necessity. In the case of his partner, Christopher Corbone, he shot him eight times even when he was already dead, which effectively emptied out the handgun's magazine; it was a definite sign of overkill brought by a state of panic following Corbone's attempt on his own life.
Eddie may have been inspired by James DiMaggio, who abducted a sixteen-year-old girl named Hannah Anderson in National City, California, on August 4, 2013, after killing her mother Christina and younger brother Ethan hours earlier in nearby Boulevard; Hannah was later rescued in the Idaho wilderness while DiMaggio was shot dead by police. Both had fathers whom they were named after, who committed suicide, and they would later copy the circumstances of their fathers' suicides (although DiMaggio was partially successful). The scenario of Samantha being in constant contact with Eddie (usually whenever she couldn't get along with her mother) and willingly coming with him also seems to based on Hannah Anderson's contact with DiMaggio, and also accusations that she willingly went with DiMaggio and was even aware of her mother and brother's murders. Also, Eddie and Samantha's relationship as father and daughter seems to be an allusion to the assumption that DiMaggio may have been the actual father of Hannah and Ethan. In an unrelated note, both Eddie and DiMaggio share the same middle name of Lee.
- Several unspecified charges of assault prior to Route 66
- Committed numerous victimless vehicle thefts and store robberies prior to Route 66
- October 22, Chicago, Illinois: Christopher Corbone (his partner; shot once in the chest and seven times in the back when he tried to kill him)
- October 23, Wichita, Kansas: Tommy Burns (Samantha's boyfriend; assaulted and attempted to bludgeon with a crowbar, but relented after Samantha yelled at him)
- October 24, Texas:
- Unspecified location: Unnamed police officer (intended to shoot)
- Amarillo: Damon Turner (incidental; was shot twice in the head and chest)
- El Paso: Unnamed man (shot in the stomach while in a struggle with him; stole his car and wallet)
- Eddie is similar to Curtis Banks in the sense that both were spree killers who had fathers they were named after who later died, deaths that would later inspire them to commit their killing sprees. Both also committed at least one act of assault prior to their killings, and shot their victims (including a gas station employee and a man they were associated with) to death. In addition, their last victims were men who were killed out of necessity. Also, Eddie's wife divorcing him because of his financially-motivated crimes is an allusion to Curtis's wife wanting to divorce him because of his gambling addiction.
- The fact that Eddie was found next to his dead father, having been sitting beside it for days, is also similar to Roderick Gless, a serial killer from Season Four, who was found next to his dead nanny Abigail, having also been sitting beside her body for days.