It's About Time is an American fantasy/science-fiction comedy TV series that aired on CBS for one season of 26 episodes in 1966–1967. The series was created by Sherwood Schwartz, and used sets, props and incidental music from Schwartz's other television series in production at the time, Gilligan's Island.

Two astronauts, Mac McKenzie (Frank Aletter) and Hector Canfield (Jack Mullaney), travel faster than the speed of light, resulting in being sent back in time to prehistoric days. There, they have to adjust to living with a cave family led by Shad (Imogene Coca) and Gronk (Joe E. Ross).

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