"A Downtown Holiday Film Celebration" features screenings Saturdays at the Harris Theater, 809 Liberty Ave. The film this Saturday will be "White Christmas" (1954) with Danny Kaye and Bing Crosby. Sponsored by the Pittsburgh Cultural Trust, Pittsburgh Downtown Partnership and Pittsburgh Filmmakers, films will be shown at 2 and 4:15 p.m. Tickets are $6 per person per film; an advance family package for $20 guarantees four seats to the movie. Tickets are available at the Box Office at Theater Square, 655 Penn Ave., or by calling 412-456-6666.

Rangos Omnimax Theater at the Carnegie Science Center, One Allegheny Ave. next to Heinz Field on the North Side, is showing "Mummies: Secrets of the Pharaohs," "Wild Ocean" and "The Alps." "The Polar Express: The IMAX Experience" will be shown at limited times through Dec. 31. Admission cost varies. Omnimax is not recommended for children younger than 3. Call 412-237-3400 for show times.