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 was a main cast member until the series ended in 2011. 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.