Name at birth: William Oliver Campbell
Actor William "Billy" Campbell is known mostly for his many television roles and for the title role in the 1991 hero adventure The Rocketeer. He grew up in Virginia and studied illustration at Chicago's American Academy of Art. He got his start in television during the 1980s, with regular roles in Dynasty and Crime Story. Although Campbell is probably best known for the cult classic The Rocketeer, most of his work has been on the stage and in television. For three seasons he played great dad Rick Sammler on Once and Again (1999-02), then had a recurring role during the run of the sci-fi mystery series The 4400 between 2004 and 2007. In recent years, Campbell played a politician on the cable series The Killing (2010-12) and a doctor in the medical thriller series Helix (2014).
According to StarTrek.com, Billy Campbell almost nabbed the role of William T. Riker in Star Trek: The Next Generation; the role went to Jonathan Frakes.