"I meant what I said about my luck turning around. It's going to, I can sense it."
In 1988, Curtis's father, Curtis Banks, Sr., who taught him how to gamble, hit the jackpot gambling and abandoned his family, taking the money with him and going to Las Vegas. Only six months later, the senior Banks became broke and drank himself to death. Not much else is revealed about Curtis's personal life, other than that he was a longtime friend of Eddie Langdon, with whom he was a partner in a failed plumbing firm called 88 Plumbing. He held down several other jobs for short times; he lost one of them directly prior to "Snake Eyes" for punching his own boss. Curtis was also a very compulsive gambler, losing a lot of money at casinos in Atlantic City. His dream was to win a jackpot and use the winnings to take his wife Teri on a trip to Tahiti. Unfortunately, his gambling problem cost him and Teri a lot of money to the point that their house faced foreclosure. He apparently managed to pull himself together, albeit only for a brief time. In 2012, on his way to a job interview in Philadelphia, he bought a scratch ticket, winning $250 and falling off the wagon again. He planned to get more money for the Tahiti trip by winning a high-stakes poker tournament in Atlantic City, which had a $50,000 buy-in and a prize sum of one million dollars. In order to fund his gambling, he had to borrow money from a low-ranking mob member, Danny Savino.
However, Curtis lost a game, which caused him to snap. As a result, he robs and then murders Savino, bludgeoning him with a trophy before leaving eight dollar bills in a circle around his body and an eight of hearts on the body for unknown reasons. Because Savino's death could cause a mob war, this leads to the BAU being called in. When Curtis gambles again, he experiences a string of victories that overjoys Eddie, who came along with him for the job interview. He is later approached by Teri, who says that they can't pay the mortgage and the bank is foreclosing on them. Curtis tells Teri that there is a poker tournament, which will get him to win a lot of money and then he will be done with gambling afterwards. Teri tells Curtis that she wants a divorce and that she is going to her sister's. Shocked by the news, Curtis begins to lose games. He eventually approaches a hooker that was previously "all over him" named Patricia Riolo, in a parking garage and bashes her head against her car window before leaving an eight of diamonds on her body and, again, eight dollar bills around her in a circle.
When he meets up with Eddie again, Eddie notices a connection in which the victims were all related to Curtis, but fails to identify Curtis as the killer. Simultaneously, Curtis begins experiencing another winning streak. Thinking that he must kill again to keep up the winnings, Curtis acquires a handgun from a man named Jimmy. During the following evening, he uses it to shoot a gas station cashier, presumably chosen at random, to death and leaves behind his now-signature. However, he continues to lose and realizes that he must murder those closest to him, as Savino and Riolo were connected to him personally. As a result, he lures Eddie into an alleyway, gives him an expensive watch as a present (Eddie had previously seen the watch and expressed his desire of having it), and remorsefully shoots him twice in the back when he has it turned on him. He then leaves behind two eight cards this time, presumably to give a "boost" to his luck. Soon afterward, Curtis also kills a high-stakes gambler and robs him of $50,000, leaving behind $20,000 belonging to him.
Using the gambler's $50,000 to buy into the poker tournament, Curtis gambles again and an undercover Reid joins the game. Reid eventually identifies Curtis as the unsub when deducing that he is being overprotective of a black 8-ball key chain. Reid leaves, secretly alerting the rest of the team, but Curtis flees, killing one of the casino's chefs in the process and stealing his jacket for a quick disguise. Desperate for luck, Curtis decides to kill the one closest to him: his wife Teri. Fleeing to the house of his sister-in-law, Liz Dorsey, he finds both Teri and Liz there and holds them hostage, ranting at the former about how she ruined his winning streak. Rossi enters the house and tells Curtis to release Teri and Liz and that he will take their place, but Curtis only releases Liz and then holds Rossi at gunpoint. Rossi attempts to appeal to him, telling him that his father was the reason behind his actions, not Teri. Hotch, Prentiss, and JJ then enter the house and order Curtis to put the gun down. Curtis looks at the clock, sees that 8 o'clock is nearing, and then looks at the mirror, to which he finally realizes that he is holding his own wife at gunpoint, intending to kill her. Flashing back to all of his killings, then to a moment where his father taught him how to gamble (thus explaining his obsession with the number 8), Curtis realizes that he has become his father and releases Teri. Now seeing that it is 8 o'clock, he pulls the gun on himself and commits suicide, which devastates Teri.
Curtis targeted people that he believed jinxed him and took his luck in gambling away. Usually, these people were associated with him in some way. He would kill those victims by bludgeoning them to death with some incidental object, such as a trophy or even the victim's own car. Later, as he began developing his "system", Curtis would shoot them with a handgun. His signature was taking the eight one-dollar bills from their wallets and lay them in a circle around the bodies, and leaving a playing card on their bodies, usually an eight of something. When Curtis killed his friend Eddie, he shot him from behind out of remorse for him and left $88 in a circle around the body and two eight cards on the body, the extra amount of money and the two cards presumably acting as some sort of "boost" to his luck. However, while he targeted those that he was associated with, as said above, Curtis wasn't hesitant in killing random victims as well. When he would do so, he would just snap their necks and not leave behind the one-dollar bills and cards of eight, in order to ensure that these kills didn't "count" in his system. The only exception to this rule was the gas station cashier, Harvey Redland, due to the fact that Curtis didn't fully recognize his system yet.
The unsub is a compulsive male gambler aged in his 30s or 40s who is targeting people who prey on or take advantage of gamblers, such as loan sharks and call girls. The killings may have been triggered by recent gambling losses. Because he is able to use such brutal and violent force, he is probably physically fit. Since he is able to move around in one of the most surveyed locations on the planet (a casino) without fear of being recognized, he probably doesn't have a criminal record, nor does he have a very domestic life with a wife and children; that would only moderate or stabilize his pathological behavior. As a compulsive gambler, he is extremely superstitious and will not be able to stop his actions on his own. The number eight, his signature that he leaves behind, seems to be a compulsion to him has some significance to himself, such as a birthday or an important event in his life. Not only is he an addict, but he is also a killer, and based on how many victims and how quickly he has killed, he is not likely to stop. The unsub basically believes that killing people and leaving the dollar bills and playing cards on their bodies gives him luck in gambling. Because his luck did not improve when he killed Harvey Redland, he also figures that the closer he is to his victim, the more luck he receives.
- January-February: An unnamed ex-employer (assaulted; punched his face)
- February 7: Danny Savino (a mob member and loan shark; bludgeoned at least three times with a trophy in his office; an eight of hearts was left on his body; robbed of an unspecified sum of money)
- February 8: Patricia "Francesca" Riolo (an escort; bashed her head on her car window twice in a parking garage; an eight of diamonds was left on her body)
- February 9: Harvey Redland (a gas station cashier; shot three times in a random attack in a gas station convenience store; an eight of spades was left on his body)
- February 10:
- Eddie Langdon (his best friend and ex-business partner; shot twice through the back in an alley; left $88 in a circle around him and two eight cards on the body)
- The unnamed high-stakes gambler (snapped his neck in his hotel suite; robbed of $50,000; Curtis's own $20,000 were left behind; did not leave any eight cards on his body)
- Unnamed casino chef (incidental; killed in a kitchen, apparently by snapping his neck, then stole his jacket)
- The standoff at Liz Dorsey's house:
- Liz Dorsey (his sister-in-law; held at gunpoint; was released)
- Teri Banks (his wife; held at gunpoint and intended to kill; was released)
- David Rossi (briefly held at gunpoint)
- Curtis is similar to Season Five criminal Bill Hodges. Both were psychotic spree killers whose crimes were financially motivated (Bill would con people out of their money; Curtis killed people to increase his gambling luck), had M.O.'s that sometimes involved bludgeoning victims, and constantly had guilt-ridden flashbacks to their murders.