He appeared in smaller independent films, working with Calista Flockhart in "Jane Doe", Chris Penn and Jeffrey Wright in "Cement" and in the 2000 Sundance Film Festival fave, "Backroads". In 1999, Martini wrote, co-directed and starred in "Desert Son". His younger brother, Christopher, co-directed the film with him and his sister, Michelle, served as costume designer. He had a recurring role in the ABC drama, "Castle". In 2011, the Noor Iranian Film Festival in Los Angeles invited him to participate as an official festival judge. In 2013, he played the role of the U.S. Navy SEAL commander in Paul Greengrass' Academy Award nominated film "Captain Phillips".