When he turned 19, Watson moved back to Los Angeles, where he worked parking cars at a House of Blues nightclub while auditioning for roles. He landed guest spots in several television series such as Baywatch and Sister, Sister. Eventually he was chosen for a minor role on the Aaron Spelling series Malibu Shores. Though his role was brief, it led him to Aaron Spelling's next project 7th Heaven. It was on the WB's 7th Heaven that Watson finally gained recognition as Matt Camden. In 1999 he starred in his first feature film with fellow WB star Katie Holmes in Teaching Mrs. Tingle. Watson left 7th Heaven in 2005, but has continued to guest star. On April 16, 2006 Watson starred as the lead character Brian Davis, in the ABC series What About Brian. The show ended its run on March 26, 2007. Currently, Watson is starring as Todd in the new ABC series Samantha Who?.