Tucker also had a significant impact upon the very origins of Doctor Who. Despite a lack of screen credit, he was the programme's first producer. Appointed in May 1963 as an "interim" or "caretaker" producer until Sydney Newman could find a permanent replacement, Tucker was also, for many months, the director of An Unearthly Child. Had the show been filmed for its original 24 August 1963 launch date, he would have been Doctor Who's first director.