In his first screen role since departing "CSI: Crime Scene Investigation," William Petersen has joined the cast of Tony Kaye's indie drama "Detachment."

"Mad Men's" Christina Hendricks and Lucy Liu also have come aboard.

Kaye, the hard-edged director who made "American History X," has assembled an ensemble cast for his high school-set drama that includes Adrien Brody, Bryan Cranston, James Caan and Marcia Gay Harden.

Carl Lund's script centers on a normally detached substitute teacher (Brody) who becomes invested in the students and teachers at the troubled school where he works and grows close to a homeless teen working as a prostitute.

Petersen will play a Vietnam veteran who teaches history. The character gets in trouble when, in a bid to teach tolerance, he shows a gay film in class.

Hendricks will play a teacher who urges Brody to commit to teaching full-time and might be a romantic interest. Liu will play a school psychologist who grows frustrated with her students' incompetence.

Bingo Gubelmann, Austin Stark, Benji Kohn and Greg Shapiro are producing the film, which recently began shooting in New York.

Petersen, repped by UTA, played police investigator Gil Grissom for a decade on CBS' "CSI." He left the show last year, turning his attention to stage work in Chicago. He recently completed a run of "The Endgame" at the Steppenwolf Theatre after starring in "Blackbird" at the Victory Gardens and in "A Dublin Carol," also at the Steppenwolf.

Hendricks, nominated for an Emmy for her work on AMC's "Mad Men," recently wrapped the feature "Life as We Know It," starring Katherine Heigl and Josh Duhamel. She is repped by the Kohner Agency and Kritzer Levine Wilkins Griffin Entertainment.

Liu appeared in "Dirty Sexy Money" and will return to voice the character Viper in the sequel to "Kung Fu Panda." She is repped by WME and Untitled.