 Peter Davison starred as the Fifth Doctor starting in the nineteenth season alongside Matthew Waterhouse, Sarah Sutton and Janet Fielding, before Waterhouse departed when Adric was dramatically killed off in "Earthshock".In "Mawdryn Undead", a new companion called Vislor Turlough was introduced, played by Mark Strickson.Sutton stepped down from the role of Nyssa in "Terminus" and Kamelion, an unusual robotic character voiced by Gerald Flood, was introduced in "The King's Demons".