He had a starring role in Gus Van Sant's Columbine-based film Elephant, which was awarded the Palme d'Or prize in 2003. Since Elephant, Frost has worked on a number of films, including The Queen of Cactus Cove, The Lost and The Standard. He appeared in a Season 3 episode of NCIS entitled "Ravenous". He played the primary antagonist in the Owen Wilson movie Drillbit Taylor, released on March 21, 2008, by Paramount Pictures. He appeared in two films in 2009, Calvin Marshall and The Vicious Kind. He recently appeared in The Wheeler Boys, premiered in the 2010 LA Film Festival. Frost is currently living in London.