Kryten is a fictional character in the British science fiction situation comedy Red Dwarf. The name Kryten is a reference to the head butler in the J.M. Barrie play The Admirable Crichton. Originally referred to as a Series III mechanoid, he is later described as a 4000 Series, or Series 4000. In their original plan for the series, Rob Grant and Doug Naylor had specified that there would be no aliens and no robots. Following the success of the first appearance by the Kryten character, Naylor convinced Grant to bring him back.