 Ruivivar's early appearances include the films "Race the Sun" (1996) and a minor character in "Starship Troopers" (1997).Ruivivar's breakthrough role came in 1999 as Carlos Nieto, a paramedic in the action/drama series "Third Watch" (1999–2005), which centers around the life of police officers, paramedics, and firemen of a fictional precinct and fire station in New York City.In the show, Carlos was a Hawaiian-born Filipino-American who was abandoned by his family and spent his youth in various foster homes.