Emily Prentiss

Emily Prentiss is a Special Agent with the BAU.

Background
In her first appearance, she recognizes Hotch from one of his first commands: security clearances for her father, a US diplomat. Her arrival surprises both Hotch and Gideon, as neither of them had signed off on the transfer. Prentiss insists her parents have not pulled strings for her. Ultimately, she joins the team at the end of episode 209 ("The Last Word") on a probationary basis as a replacement for Agent Elle Greenaway. She is a graduate of Yale and has been working for the FBI for little under ten years, primarily in the Midwest. Due to spending her early life with her parents on diplomatic missions to the Middle East, she speaks fluent Arabic and is familiar with that area's local culture. She also speaks some Russian, Spanish, French, and Italian. She appears skilled at chess, and it is possible that she is better at the game than Reid. JJ once asked Prentiss how she could handle the stress from being with the BAU, especially since her last position was a desk job. Hotch concurred that she had "never blinked," and Prentiss could only reason that she "compartmentalizes better than most." ("Revelations") After a bad date in the following episode, she admits to Derek Morgan that she is a "nerd," despite how much she tries to hide it. For this reason, she hasn't had much success romantically. She discovers that she and Morgan share similar tastes in books when they begin discussing Kurt Vonnegut, particularly Slaughter House 5.

On the Job
At the end of season 2, BAU section chief Erin Strauss reveals to Emily that she arranged for her to join the BAU, contrary to Emily's belief that she was accepted on her own merit. Strauss asks Emily to sabotage Hotch's career by spying on him and relaying confidences back to Strauss, especially concerning Elle Greenaway's shooting of a suspect and Reid's struggle with narcotics. She seems to consider this offer, and the season ends with a cliffhanger until the second episode of season 3, in which she resigns from the FBI to avoid betraying Hotch. She decided later not to resign and is still a current main character.

Season Three
Emily has previously told Hotch that she thinks politics "makes people distrustful" and "tears families apart," ("Sex, Birth, Death") implying that her home life as a child was not pleasant due to her mother's job. After some convincing from Hotch she returns to the team in the next episode, her resignation having never gone through system due to technical interference from Garcia, and the issue has not been brought up since. Upon her return, Section Chief Strauss remarks that neither Prentiss, Hotch, nor the rest of the team would be able to climb the ladder to the top because of all this, thus putting an end to some of Prentiss's future ambitions. In episode 319 ("Tabula Rasa") a high school photo reveals that Emily was a goth or emo. Also, in episode 312 ("3rd Life"), she implies to Hotch that she smoked as an adolescent as a way to rebel against her parents. In the season 3 finale "Lo-Fi", she shoots and kills an armed suspect after the suspect shoots a New York police officer.

Season Four
In season 4 episode 3 (Minimal Loss) she and Reid are held hostage by a religious cult. When the cult leader finds out that one of them is an FBI agent, Prentiss admits her identity, partially to protect Reid, and ends up getting beaten by the cult leader. Prentiss antagonizes the leader by twice repeating "I can take it" to keep the rest of the team from coming in, knowing that they are listening via bugs and that it would put everyone inside of the building in danger. Later, Prentiss reassures Reid that it was not his fault and asks him not to feel guilty.

Season Six
In The Thirteenth Step, Prentiss learns from a former colleague at Interpol, Sean McCallister, that Ian Doyle, an apparently highly dangerous criminal, has escaped from his Russian prison and gone off the grid after killing a man and stealing his car. Sean warned her that he might come after her and that everyone is in danger. Doyle is set to reappear in upcoming episodes. In the beginning of Sense Memory, she opens a safe in her apartment. It contains a USB flashdrive, some passports, and a manilla envelope containing a stack of papers, the first of which is a profile with her photo. Everything else, besides "Citizenship: Belgium" below the image, has been obscured. Attached to the papers is also a mugshot of Ian Doyle. When her cat, Sergio, comes in all soaked, she realizes that someplace in the apartment is open and begins searching with a gun in her hand. Finding an open window, she closes it and calls her catsitter, who confirms that she left the window open so Sergio could come out. When the phone rings and the caller ID is unknown, Prentiss lets it go to message and listens to the recording. The caller, presumably Doyle, is completely silent and hangs up. In response, Prentiss sets up some noisetraps near all entrances and exits in the apartment, sits down in the hallway with a gun, turns off the lights and waits.

When Prentiss returns to her apartment after the case is concluded, she finds a package by her door. Reid then calls and asks her out for Solaris, a Russian sci-fi movie. At first, she is suspicious that he just called her out of the blue, but then turns him down, saying she will spend the evening with Sergio. When she opens the package, it turns out to contain a small, purple-white flower. There is a flashback to some time earlier when she, using the alias "Signorina Reynolds", is working in a flowerbed filled with the same flowers, apparently by a mansion somewhere in France. When authorities, presumably Interpol, arrive and drive away with her, she asks for Sean while Doyle watches her from a balcony. He calls someone and tells about her, saying she either works for CIA, MI5, ICC or Interpol and tells the other person to "stay on on top of [it]". As he is arrested by English-speaking authorities, he looks down at one of the flowers that Prentiss dropped. Back in the present, Prentiss packs the envelope in a bag, takes Sergio and leaves her apartment.