One of Emerson's most well-known works was in 2004, as the character Zep Hindle in the horror movie "Saw". In 2006, Emerson began guest-starring on the television series "Lost" as Henry Gale/Ben Linus . He was originally planned to be in a small number of episodes, but he returned for season 3 as a main cast member. In 2007, he was nominated for another Emmy Award for his work on the series.