[1] While in London, he formed a soul band, The Majestics, and worked as a backup singer on such hits as "Love and Affection" by Joan Armatrading, "Boogie Nights" by Heatwave, and some David Essex songs.

[2] His first West End theatre musical roles, which he received with assistance from his friend Ned Sherrin, were I Gotta Shoe (1976) and Bubbling Brown Sugar (1977).

[2] Other West End credits include Blues in the Night, Porgy and Bess, The Witches of Eastwick, Guys and Dolls, Chicago, and Chess.

His performance in The Iceman Cometh (1999) won him the Theatre World Award, and he portrayed the shady lawyer Billy Flynn in the revival of Chicago in 2000 and 2003.

In regional theatre he has appeared in Driving Miss Daisy, The Wiz, Bubbling Brown Sugar, Ma Rainey's Black Bottom, Carmen Jones, and The Amen Corner.

Peters also starred in the HBO mini-series The Corner, portraying a drug addict named Fat Curt, as well as the FX series Damages, as Dave Pell.

[9] In that year, he also had a guest appearance as Professor Mark Ramsay in the pilot episode of the USA Network TV series Covert Affairs.

Peters' movie credits include Mona Lisa (1986), Notting Hill (1999), K-PAX (2001), Freedomland (2006), Marley & Me (2008), Endgame (2009; in which he played Nelson Mandela), Nativity!

[11] He also narrated the BBC radio series Black Music in Europe: A Hidden History,[12] as well as the audiobook version of Michael Chabon's novel Telegraph Avenue, released in September 2012 by HarperAudio.

[2] As of 2012, Peters split his time between a house in the Charles Village section of Baltimore, which he bought in 2006 while working on The Wire, and one in London, where Penny and Max live.