Fitzgerald (Lobby Hero, "Dirty Sexy Money") is withdrawing from the production due to a television project. Mount joins a cast that includes Gabe Bettio, Maggie Gyllenhaal (as Masha), Josh Hamilton, Jessica Hecht (as Olga), Marin Ireland, Paul Lazar, Roberta Maxwell, George Morfogen, Ebon Moss-Bachrach, James Patrick Nelson, Juliet Rylance (as Irina), Peter Sarsgaard and Louis Zorich.

Mount's stage credits include Corpus Christi at Manhattan Theatre Club, Cymbeline at the Public, Caucasian Chalk Circle at La Mama, Fifth of July at Bay Street Theatre and Williamstown Theatre Festival, Mourning Becomes Electra at the Acorn, Elle at the Zipper and Glengarry Glen Ross at the Macha Theatre in Los Angeles.

Three Sisters, under the direction of Austin Pendleton, begins performances Jan. 12 at CSC's home at 136 E. 13th Street.

Pendleton also directed Gyllenhaal and Sarsgaard in CSC's acclaimed 2009 production of Chekhov's Uncle Vanya. The new production of Three Sisters will feature a translation by Paul Schmidt.

Opening night is Feb. 3. The production will play a limited engagement through Feb. 20. The creative team includes set designer Walt Spangler, costume designer Marco Piemontese, lighting designer Keith Parham and hair designer Paul Huntley. Sound design and original music are by Christian Frederickson and Ryan Rumery.

Three Sisters is the 1901 play about thwarted dreams, featuring three provincial sisters longing to be back in their beloved Moscow.

Three Sisters will perform Tuesdays through Fridays at 8 PM; Saturdays at 2 PM and 8 PM and Sundays at 2 PM.

Tickets are $75 for weekday performances and $80 for weekends. For tickets and information, visit www.classicstage.org or call (866) 811-4111, or (212) 352-3101, or visit the CSC box office at 136 E. 13th Street.