Movies

Joseph appeared in the Royal Shakespeare Company productions of King Lear and Love's Labour's Lost in 1990. On television he is best known for his roles in Casualty (1997–1998), as Alan Johnson in Channel 4 sitcom Peep Show (2003–2015), Green Wing (2004–2006), Survivors (2008–2010), Boy Meets Girl (2009), as DI Wes Layton in Law & Order: UK (2013–2014), as Holy Wayne in The Leftovers (2014–15), as DCI Mark Maxwell in Safe House (2015–2017), and as Connor Mason in Timeless (2016–2018). His film roles include The Beach (2000), Greenfingers (2001), Æon Flux (2005) and The Other Man (2008).

Joseph is also a writer, and his 2022 debut novel The Secret Diaries of Charles Ignatius Sancho won the 2023 Christopher Bland Prize awarded by the Royal Society of Literature.

Early life
Joseph was born on 22 June 1964 in Willesden Green, London to parents from Saint Lucia. He attended Cardinal Hinsley R.C. High School in north-west London, a predominantly Irish-Catholic school. He has described himself as a "terrible bunker" whilst at school, opting to spend the best part of two years in the local public library instead.

He worked briefly as a catering assistant at a hospital, before deciding to pursue acting as a profession. Joseph first trained at the Studio '68 of Theatre Arts, London (South Kensington Library) from 1983 to 1985 with Robert Henderson. He later attended LAMDA, before going on to perform for the Royal Shakespeare Company and The Royal National Theatre.