 Gemmill played consultant Adam Trueman in the long-running BBC medical drama "Casualty" from September 2007 to August 2011.In a "celebrity" edition of "Mastermind", aired on BBC 1 on 1 January 2010, Gemmill defeated comedians John Bishop and Ed Byrne and TV presenter Anneka Rice to win the trophy.His specialist subject was the Apollo Moon Landings.