His first notable appearances were in the British Indian sketch show Goodness Gracious Me, being the only recurring white person in the cast.
Throughout the 1990s and early 2000s he also appeared in comedy programmes such as People Like Us, Hippies, Armstrong and Miller, The Smoking Room and Fun at the Funeral Parlour as well as having a brief role in a couple of episodes of EastEnders.
[citation needed] In May 2012, he did a voice over for UK band Jackdaw4 on their PledgeMusic page, to promote their pledge campaign to record their fourth album.
In November 2013, Lamb provided a voice over for Bedford Modern School's production of "The Only Way", a play commemorating 10 years of co-education.
In 2018 Lamb was the commentator on BBC One's Saturday evening game show And They're Off ... for Sport Relief, presented by Ore Oduba.
He also played Sergeant Foster in two episodes of Only Fools and Horses prequel Rock & Chips, including the special shown on BBC One on New Year's Day 2011.
Lamb made his stage debut alongside Russ Abbot and Eric Sykes in 2003 in a production of Ray Cooney's Caught in the Net at the Vaudeville Theatre.