"Unlock the Chamber of Secrets" - Warner Bros. is holding an online sweepstakes in conjunction with its home entertainment release of HARRY POTTER AND THE CHAMBER OF SECRETS. The grand-prize winner wins a walk-on role in HARRY POTTER AND THE PRISONER OF AZKABAN. One first-place winner will receive a private, advance screening of PRISONER in his/her hometown. Consumers can enter the sweeps and receive an electronic game board and a movie scene trading card. The competition lets fans earn and trade images from the film to complete game boards to win virtual rewards and access their favorite scenes from the movie. Players can collect all three sets of cards by answering film trivia, recruiting friends to register and logging on to the site daily. Players who purchase the SECRETS DVD will also have the opportunity to collect exclusive cards. The sweepstakes runs March 28, 2003 - April 21, 2003 and is supported by TV, print, outdoor and radio advertising.