William Katt is an actor best known for his role as the star of THE GREATEST AMERICAN HERO television show. He began his career at The Tony Award Winning South Coast Repertory Theatre. He also appeared in many small roles on TV during that time. His earliest film credits include Tommy Ross in Brian DePalma's 1976 film CARRIE, and the role of The Sundance Kid in the 1979 film BUTCH AND SUNDANCE: The Early Days. He appeared in the John Milius surf film BIG WEDNESDAY opposite Jan-Michael Vincent and Gary Busey. William auditioned for the part of Luke Skywalker in 1977's STAR WARS, and footage of his audition has been featured in many Star Wars documentaries. That year he also starred in the film FIRST LOVE.

In 1981, William was cast as the title role in a filmed version of the Broadway musical comedy PIPPIN. That year, he played his best remembered role, as Ralph Hinkley, a mild-mannered schoolteacher given a super powered suit by aliens on the television series THE GREATEST AMERICAN HERO.  In 1986 William starred in the cult horror/comedy film HOUSE and played the recurring role of detective Paul Drake Jr. in the periodic PERRY MASON TV movies of the late eighties. These co-starred his mother actress Barbara Hale, who resumed her Della Street role from the original show. He carried in the 1989 TV series TOP OF THE HILLl, and acted in the 1991 series GOOD SPORTS.

William continues to appear on television and in supporting film roles and has also branched out into directing and voice acting. In recent years he has returned to genre work, with appearances in ANDROMEDA and JUSTICE LEAGUE and roles in the 2006 award-winning film GAMERS,and the 2007 THE MAN FROM EARTH. William also briefly appeared in HEROES season 3, THE BUTTERFLY EFFECT. Forthcoming he stars opposite Elliot Gould in THE ENCORE OF TONY DURAN a recent Jury Prize Winner at the Las Vegas Film Festival - and he joins a stellar ensemble action comedy cast in the soon to air web series MOON.