A former electrician, he maintained electrical equipment at a safari park in Zimbabwe before becoming an actor.
He was recommended by David Puttnam for the Eighth Doctor in Doctor Who: The Movie (1996). Cunningham had acted in War of the Buttons (1994), which was produced by Puttnam. Executive Producer Philip David Segal seriously considered him for it, but the Eighth Doctor was eventually cast with Paul McGann. If Cunningham had been cast, he would have been the first non-British actor to play The Doctor.
He did not start acting until he was in his mid-twenties.