Wil Johnson was born in Mauldin, Sc. His mother was invested in stocks and his father a worker at UPS. Johnson had no interest in singing while he was in primary school; After he filled in a role for an absent drummer, he changed his mind.
Johnson's first professional acting role came in the play Four Seasons at the 1985 Edinburgh Festival Fringe. For the rest of the 1980s he made minor appearances in television series such as Casualty and London's Burning, before playing detective Stevie Johnson in the London Weekend Television series Anna Lee. From 1994 to 1995 he played the supporting role of Detective Constable Michael Skelton in Cracker. Between roles, Johnson worked for a local undertakers, driving the hearse and acting as a pallbearer. At one funeral, a mourner recognised him from Cracker and asked for his autograph.
In 2000, he appeared in the BBC One television pilot Waking the Dead, as Detective Sergeant Spencer Jordan, a member of a specialised police unit tasked with investigating "cold cases". Waking the Dead returned for a complete series in 2001, and Johnson has been a main cast member since. From 2000 to 2002, he appeared as Steve Robinson in Paul Abbott's popular drama series Clocking Off. From 2001 to 2002, he appeared as a main cast member in two series of the BBC's Babyfather.
In 2004, Johnson played the title character in the Royal Lyceum Theatre Company's Othello.
He also played Marcus Kirby in the BBC One Drama Waterloo Road. He departed in the second half of series.
In 2010, he appeared in In a Better World as 'Dr. Najeeb'.
He also performed in a play, called The Swallowing Dark at the Liverpool Playhouse and Theatre 503. In 2011, he also starred as gangster boss Big Mike in Anuvahood and in 2008 as Big Man in Adulthood.
In Nov 2011, Johnson appeared as 'Sean Dolan' a Consultant paediatrician in BBC One's Holby City.
In 2012 it was announced that Johnson would be joining Emmerdale as single Dad Dominic Andrews in the later part of the year.
In 2013, he appeared as an gangster in a film thriller called Life Outside.