He is most notable for his portrayal of Roland "Prez" Pryzbylewski for five seasons of The Wire. He also also appeared in an episode of David Simon's Homicide: Life on the Street.
A New York-based actor, True-Frost has been an ensemble member of the Steppenwolf Theatre Company in Chicago since 1989. Prior to that, he was a member of Remains Theater, co-founded by actor William L. Peterson (To Live and Die in L.A., CSI: Crime Scene Investigation), where he worked with such performers as Amy Morton, Gary Cole, and D. W. Moffett. True-Frost appeared in the film Off the Map — with fellow Steppenwolf ensemble member, Joan Allen, directed by Singles co-star Campbell Scott — Affliction, The Hudsucker Proxy, Singles, Normal Life and Far Harbor. He has performed on Broadway and as far away as Sierra Leone.
True-Frost appeared as Brutus in the American Repertory Theatre's production of Julius Caesar in 2008.