Grant has twice portrayed the Doctor from Doctor Who, both outside the main continuity. In the comedy Sketch Doctor Who and the Curse of Fatal Death, he portrayed a version of the Tenth Doctor, referred to as the Quite Handsome Doctor. He also voiced a version of the Ninth Doctor for the BBC original animated webcast Scream of the Shalka. The latter had intended to be the official Ninth Doctor prior to the revival of the TV series. In August, 2012, the BBC announced that Grant would join the cast of Doctor Who for "The Snowmen", in which he plays a villain, Dr. Walter Simeon. He appeared again in the following episode, "The Bells of Saint John" as the Great Intelligence, one of the Second Doctor's most infamous villains and, prior to "The Snowmen" (played by Ian McKellen), was last seen in The Abominable Snowmen and The Web of Fear. Grant reprises the role in the series 7 finale, "The Name of the Doctor".