Michael Jayston played the Valeyard in the Doctor Who stories The Mysterious Planet, Mindwarp, Terror of the Vervoids and The Ultimate Foe. He reprised the role in He Jests at Scars..., Trial of the Valeyard and all four stories of The Sixth Doctor: The Last Adventure produced by Big Finish Productions. He played the Tsar in Tsar Wars in Serpent Crest. He went on to play Donald De Souza in Emmerdale, contemporaneously with Jenna Coleman's performance as Jasmine Thomas.