The series begins with two bumbling United States astronauts, (Frank Aletter) and Hector Canfield (Jack Mullaney), whose space capsule, Scorpio , accidentally breaks the time barrier after traveling faster than the speed of light. They crash-land in a prehistoric swamp on Earth, roughly a million years in the past.
(Mary Grace) and Breer (Pat Cardi), their teenage children.
The episode focuses on the astronauts’ first attempts to bridge the cultural gap between the 20th century and the Stone Age. Specifically, Mac and Hector try to introduce modern birthday customs to their new prehistoric friends, leading to the comedic confusion of the episode's title. It's About Time (TV Series 1966–1967) - IMDb