Larkin played Cambridge in three series of John Sullivan's Roger Roger for BBC1 and George Marsden in Charles Sturridge's critically acclaimed Shackleton for Channel Four. Larkin also appeared in the 2007 episode of Doctor Who "The Shakespeare Code" and the 2012 low-budget horror film The Facility (originally titled Guinea Pigs) directed by Ian Clark.
In 2013 he starred in the television revival of Yes, Prime Minister as Bernard Woolley., reprising the role he had played in the Gieguld Theatre in London's West End.
