Four of the five guest stars went on to star in their own series. Robert Culp played Kelly Robinson in I Spy (1965), Agnes Moorehead played Endora in Bewitched (1964), Jonathan Harris played Doctor Zachary Smith in Lost in Space (1965), and Martin Landau played Rollin Hand in Mission: Impossible (1966) and Commander John Koenig in Space: 1999 (1975). Only John Abbott remained forever a character actor.