Comtra Theatre, Route 19 in Cranberry Township, will present the musical "Sweeney Todd" from Jan. 9 to 17 at the theater on Route 19. Curtain is at 7:30 p.m. Fridays and Saturdays. Admission is $12 for plays and $15 for musicals. Box office opens at 6:45 p.m. the day of the show. Call 724-773-9896.

<B>City Theatre</B> heralds the return of "Sister's Christmas Catechism," by Maripat Donovan, through Sunday at City Theatre's 252 seat main stage. Kim Richards reprises her role as Sister in an evening filled with laughter and the infamous "Living Nativity" involving audience members. Call for the Christmas week schedule for the show at the City Theatre, Bingham and 13th Streets on the South Side of Pittsburgh. Tickets range from $35 to $60. Call 412-431-2489.<B>"Frost/Nixon,"</B> the 2007 Tony Award-nominated play by Peter Morgan, concludes on Sunday at the Benedum Center, 719 Liberty Ave. Stacy Keach takes on the role of President Richard Nixon and is joined by British actor Alan Cox as David Frost. Curtain is at 8 p.m. Friday; at 2 and 8 p.m. Saturday; at 1 and 6:30 p.m. Sunday. Tickets range from $20.50 to $54.50 and are available by calling 412-456-6666.<B>The Backstage Bar and Cabaret at Theater Square</B>, a project of The Pittsburgh Cultural Trust, in Theater Square at 655 Penn Ave., is staging "I Love You, You're Perfect, Now Change," through Feb. 1, at the CLO Cabaret, 655 Penn Ave. Performances start at 7:30 p.m. Wednesdays through Saturdays, at 2 p.m. Saturdays and Sundays and at 1 p.m. select Thursdays, except some holiday dates in November, December and January. Tickets are $39.50 for evenings or $34.50 for matinees. Call 412-456-6666 or visit the Web site, CLOcabaret.com.