Opening this week

     Head On
     
      A young man (Alex Dimitriades) struggling with his ethnic identity, his parents and their expectations -- and his homosexuality -- embarks on a drug- and sex-filled rampage that fuels this night-in-the-life odyssey, which marks Ana Kokkinos' directorial debut and earned Dimitriades best actor honors from the Film Critics Circle of Australia. (104 min.) NR; sexual situations, violence, drug use.
     
     Knockout
     
      Las Vegas-based filmmaker Lorenzo Doumani co-writes and directs this drama about the daughter (Sophia-Adella Hernandez) of a former boxer, who's determined to follow her father's fancy footwork and win the championship he gave up for his family. Eduardo Yañez, Tony Plana, William McNamara, Maria Conchita Alonso and Paul Winfield co-star. PG-13; boxing violence, profanity, brief drug content.
     
     Liberty Heights
     
      Writer-director Barry Levinson returns to his Baltimore roots for the fourth time -- following "Diner," "Tin Men" and "Avalon" -- for this comedy-drama about a Jewish family caught in the crosscurrents of a changing America at the dawn of the civil rights era in 1954. Tony-winning stage veterans Joe Mantegna and Bebe Neuwirth head the family, while Ben Foster (Disney TV's "Flash Forward") and Adrien Brody ("Son of Sam," "The Thin Red Line") play their sons, each of whom learns a bittersweet coming-of-age lesson. (127 min.) R; profanity, sexual references, mature themes. (Reviewed in this edition.)
     
     Scream 3
     
      Director Wes Craven wraps up his smash terror trilogy as a series of murders draws returnees Sidney Prescott (Neve Campbell), Gale Weathers (Courteney Cox Arquette) and Dewey (David Arquette) to the Hollywood set of "Stab 3," the movie inspired by the events they survived in the first two chapters of "Scream." Parker Posey, Scott Foley, Emily Mortimer, Matt Keeslar, Jenny McCarthy, Deon Richmond, Patrick Dempsey and Liev Schreiber round out the starring cast. R; strong horror violence, profanity.
     
     Sweet and Lowdown
     
      Sean Penn's acclaimed performance powers writer-director Woody Allen's latest, a droll "Zelig"-style mock documentary portrait of Emmett Ray, a fictional 1930s jazz guitarist whose artistic gifts far outstrip his personal morals. Samantha Morton (also earning raves for her performance as Ray's mute girlfriend) and Uma Thurman co-star. (95 min.) PG-13; sexual situations, substance abuse.
     
     -- Carol Cling