The vagrants were initially a loosely defined community living in the sewers of Las Vegas, Nevada. All of them were out on the streets for various reasons. They were formally, implicitly organized by a new resident named Marvin Caul, a former, disgraced magician who went underground due to feeling unappreciated in his job. He was assisted by one member, Carrie Bailey, but he eventually killed her after she decided to leave for another magician. Then, he hypnotized another member, Cesar Jones, and had him believe Marvin was a powerful being called "The Doctor" as intimidation for Cesar and the other vagrants. Under his and Cesar's reign, the vagrants committed a series of pick-pocketing crimes against Las Vegas citizens, and they were forced to donate a sizable portion of the money to Marvin, who would use it to fund a show at the Rio All Suite Hotel. All the while, they remained unaware that Marvin was "The Doctor", while Marvin continued to pose as another ordinary member.
Prior to the beginning of the episode, Renee Sheffield was murdered and dumped at the dump site by Cesar under Marvin's orders when she was planning to leave the organization. Afterwards, another member Frida Bancroft was planning on leaving the organization as well and is seen being tied to a pipe and begs Cesar not to kill her, telling him that she will do anything, but Cesar tells her that it is too late, and then he kills her and dumps her body at the dump site. As the BAU are called in to investigate, another member named Elijah Hall yells for help in a drainage, but no one hears him and he is killed by Cesar as well. Finn Bailey joins the organization after receiving an invitation by Marvin. However, the reason Finn joins the organization is to find his sister, Carrie. So, he follows him to the sewers and sees many vagrants as well. The next day, the vagrants line up as Cesar holds a bag when the vagrants give him valuable items and the money they pick-pocketed. Then, Sarah Renfield appears and tells Cesar that she is new and needs a place to stay for a while until she can buy a bus ticket back to Minnesota. Finn volunteers to vouch for Sarah. Later, it is revealed that Sarah is a reporter, who infiltrated the sewers to learn about the vagrants. However, she is caught by Cesar and he incapacitates her.
Then, Finn finds out that Cesar has Sarah and is about to kill her. Finn tries to stop Cesar from doing so, but Marvin appears and tells him that Finn should be the one to kill her, since he was the one who vouched for her. Later, JJ and Morgan go into the sewers to investigate. They find Cesar and they pursue him and then they apprehend him. Finn and Marvin take Sarah outside the sewer tunnels. Finn tries to reason with Marvin about not to kill her. Then, Finn pretends to follow Marvin's order and takes out a pistol. Then, he realizes that Marvin is The Doctor because he was the only one not afraid of Cesar. So, Finn points his pistol at Marvin and accuses him of his sister's disappearance. Then, the BAU show up and convince Finn to drop the pistol when they tell her that they found Carrie's body in a crack den, dead from a drug overdose in Phoenix, Arizona. However, it is revealed that it was a lie and Reid manages to get Marvin to confess of killing Carrie and is then arrested. Finn was presumably arrested for possession of a pistol and it is unknown what has happened to the vagrants when Cesar and Marvin were arrested.
The vagrants committed pick-pocketing crimes through various ways. Members were known to infiltrate casinos, posing as tourists, and take money or chips while the owners are not looking. Judging from Marvin's dialogue, another method involved one vagrant distracting hapless victims, allowing another to steal any valuable items, followed by the two of them fleeing in a getaway vehicle driven by a third vagrant. New members were only allowed to join the group if a current member vouched for them. Any members who attempted to leave were killed by Cesar under the orders of Marvin, unbeknownst to the others.
No profile of the vagrants was made by the BAU, since they were focused on Marvin and Cesar.
- Leader: Marvin Caul (incarcerated). Portrayed by David Clennon.
- Finn Bailey (infiltrated the cult to find his sister Carrie). Portrayed by Ashton Holmes.
- Sarah Renfield (infiltrated the cult to learn more about them). Portrayed by Keelin Woodell.
- Renee Sheffield (deceased). Portrayed by Kayla Crance.
- Frida Bancroft (deceased). Portrayed by Courtney Cunningham.
- Elijah Hall (deceased). Portrayed by Travis Hammer.
- Mary. Portrayed by an uncredited actress.
- Gladys. Portrayed by Karen Teliha.
- Olsen. Portrayed by Gregory Bach.
- Several unnamed others
- Numerous unnamed people (all robbed)