NB: guba.com, which had the full episode no longer exists and the video has been replaced with some available, relevant YouTube videos.
It's About Time was a short-lived Sherwood Schwartz comedy about a pair of astronauts (Frank Aletter and Jack Mullaney) traveling back in time to cavepeople (Imogene Coca and Joe E. Ross) days. The astronauts spend their time try to repair their spaceship and return to the 20th century while dealing with the local troglodytes … with expected hilarity.
In the middle of the season the astronauts fix their ship and return to modern times with Coca and Ross for some desperate old-fashioned TV show retooling.
The show was canceled about six months before I was born, and because with only 26 episodes it never made it to syndication, so I never saw it before. I had seen stills in some books and photos of the lunchbox. And knew the reference to the show in "I Must Not Think Bad Thoughts" by X.It's standard Schwartz — simple characters, simple jokes and a theme song that explains the show.
The best part is the animated into, and the song's kinda catchy too.