Stephen Hartley Dorff Jr. (born July 29, 1973) is an American actor. Starting his film career as a child, appearing in the cult horror film The Gate (1987), Dorff first rose to prominence playing Stuart Sutcliffe in Backbeat (1994) and then gained further mainstream attention for portraying Deacon Frost in Blade (1998). Other notable lead roles include Bob Rafelson's Blood and Wine (1997), the titular character in John Waters' Cecil B. DeMented (2000), and Johnny Marco in Sofia Coppola's Somewhere (2010), as well as Britney Spears’ boyfriend in her 2004 music video for "Everytime".

Supporting roles include Candy Darling in I Shot Andy Warhol (1996), Detective Scott Strauss in World Trade Centre (2006), Homer Van Meter in Public Enemies (2009), Stavros in Immortals (2011), Joseph Kuklinski in The Iceman (2012), and Ketchum in Old Henry (2021). He is also known for portraying Roland West in the third season of HBO's crime drama anthology seriesTrue Detective (2019).