A Muslim FBI agent of African-American descent, Darwyn infiltrates the LA sleeper cell using the name of Darwyn al-Hakim. A former Army Ranger, he quickly wins the cell's trust, though the stress of his job threatens to compromise his mental health.
Badass: Exemplified by his takedown of several teenaged thugs on a train.
Becoming the Mask: Both Darwyn and his handlers are concerned that this might happen to him, especially in Season 2.
Deep Cover Agent: For the FBI, spending time in prison in order to fabricate an appropriate backstory.
Even Evil Has Standards: Invoked. Darwyn is, of course, a very good guy, but he pretends to be a terrorist with standards in order to convince Farik to take out a child prostitution ring.
The Masquerade Will Kill Your Dating Life: Given that he's an FBI agent pretending to be a terrorist pretending to be a reformed ex-con, it's not surprising that his relationship with Gayle comes under a lot of strain.
Where Da White Women At?: Played with. Nobody really has a problem with Darwyn's romance with Gayle on account of his skin colour (or hers). The fact that he's a Muslim, however, worries her sister and brother-in-law, while Gayle being an "infidel" has Farik urging him to break it off.
Played by: James LeGros
Played by: Sonya Walger
The FBI agent who takes over Darwyn's case after Ray Fuller left the series. A hardline cop who follows procedure to the letter, she clashes with Darwyn, who prefers to improvise his plans as he goes along. Eventually they win one another's respect and trust.
Action Girl; She's the one who actually captures Farik at the end of the first season, taking out his kneecaps rather than letting him martyr himself.
Born Saad bin Safwan, Farik is the charismatic and brilliant leader of the LA sleeper cell. A former Saudi national currently masquerading as a Sephardic Jew in his civilian life, Farik is a fanatical, but cold-blooded zealot, who thinks nothing of mass murder so long as it meets his political ends.
Bad Boss: In the first episode he has Bobby Habib executed for bragging to an uncle about their operation. He later murders Eddy Pangetsu (whom he forced into joining up with the cell in the first place)
The Big Bad: Of both seasons of the show. Yes, the rest of al-Qaeda is out there somewhere, and Farik takes his marching orders from their higher-ups, but he's the one driving all the action in Sleeper Cell.
The Chessmaster: Farik has multiple back up plans, and never lets any of the members of the cell know all the details for any of them. He typically gives each member of the cell a job to do, while keeping the master plan all to himself.
The Leader: Of the LA sleeper cell. He's a combination of Type I and Type IV, running the cell through brains and sheer force of personality.
Manipulative Bastard: Excels at playing the various members of the cell against each other, and preying on their insecurities in order to keep them in line.
Played by: Henri Lubatti
A Bosnian Muslim who saw everyone he knew butchered by Serbs during the Yugoslavian Civil War, Ilija grew to hate the United States for not intervening in the conflict. Having been rescued by Farik's team of mujaheddin during the Civil War, he is now Farik's right-hand man. He spends his days undercover as a substitute math and science teacher.
A French skinhead who converted to Islam after falling in love with a Moroccan woman, Christian simply exchanged one form of extremism for another. A brutal thug, Christian is a deeply troubled man, who regularly seeks out one-night stands, even while bemoaning the failure of his marriage.
The son of two liberal college professors, Tommy Emerson seems to have converted to radical Islam just to spite his parents. A loose cannon who possesses all the maturity of an enraged teenager, Tommy is simultaneously violent and unsure of himself, which causes the cell some problems.
Affably Evil: For all his poor social skills and anger issues, Tommy's probably the member of the group who tries the hardest to befriend the rest.
Berserk Button: Pretty much anything having to do with his mother, honestly.