''It's About Time'' (1966-67) was about two astronauts who, after breaking the speed of light, accidentally travel back in time to prehistoric Earth. Unable to return, they make friends with the "natives" in the stone age. An attempt to do a live-action version of ''WesternAnimation/TheFlintstones''.

Halfway through the season, having run out of stone-age jokes, the show was {{retool}}ed by having the astronauts manage to fix their spacecraft and return, bringing some of the stone-age characters with them, turning the show into a FishOutOfWater about stone-age characters trying to figure out modern life. This wasn't very successful either, and the show only lasted the one season.
* OneMillionBC: The astronauts accidentally break the time barrier and get stranded in One Million B.C.
* AnimatedCreditsOpening: Revamped with its plot points reversed after the {{Retool}}.
* BlazingInfernoHellfireSauce: In "Stone Age Diplomats", the food that Shad and Gronk prepare for the astronauts and the "Ambassador of Nordania". It's a mixture of everything with a generous helping of hot sauces mixed in. Naturally, the astronauts, the ambassador and the landlord choke or gulp down water. Shad and Gronk love it.
* ComicBookAdaptation: One issue long.
* ContemporaryCaveman: After Shad, Gronk, Breer and Mlor return to the 20th century with Mac and Hec.
* DecidedByOneVote: In the episode "Mark Your Ballots", Mac and Hector convince the cave-people to have an election, running Boss against Gronk. The election results in a tie, but at the last minute an old woman named Trong, who lives near the tar-pits, arrives to vote for Boss.
* EverytownAmerica: Riverview, Ohio; Lt. Hector Canfield's oft-mentioned hometown.
* ExpositoryThemeTune: ''It's About Time, It's About Flight, It's About Travelling Faster Than The Speed of Light''. In an interview, Sherwood Schwartz said it was the best theme tune he ever wrote. That's something, considering he was responsible for the iconic and well-loved ''Series/BradyBunch'' and ''Series/GilligansIsland'' theme tunes.
* FantasticComedy: Time travel, astronauts, cave-people, dinosaurs.
* FishOutOfTemporalWater: The astronauts in One Million B.C., particularly Hector who never seems to try to adapt or adjust his behavior to the circumstances. Later, Shad, Gronk, Breer and Mlor in the 20th century. It's implied, though, that they'll slowly get better.
* FishOutOfWater: Again, the astronauts in One Million B.C., and the cave-family in the 20th century.
* GettingCrapPastTheRadar: In the pilot the female Cave Dweller was named Shag. The radar then got fixed for the series in which her name became Shad.
%%* HalfHourComedy
* KissingTheGround: In "Twentieth Century Here We Come", upon landing back in the twentieth century, Hector remarks to Mac that they ought to kiss the ground, the astronauts being grateful for being back in their own time. Unfortunately, LiteralMinded cave-people Gronk, Shad, Mlor and Breer believe this is actually a ceremony one practices on the astronaut's "side of the hill." They kiss the ground.
--> '''Shad''': Strange custom.
* MachineWorship: In "School Days, School Days", Shad and Gronk make a sacrifice to the garbage disposal calling it the "god of Garbage"! At the end of the episode, after Mac and Hector enroll them in night school to catch up on a million years of civilization, Gronk mentions they're going to be taught about Edison, god of the Electric light.
* ManEatingPlant: In "Androcles and Clon", the astronauts are attacked by a man-eating plant in the jungle. The plant attacks them with its vines and tries to pull them into a thicket. Mac and Hector are able to free themselves with a little difficulty.
* MyLifeFlashedBeforeMyEyes: In "Androcles and Clon", it was said by both astronauts after a narrow escape with being clubbed and pushed off a cliff by Clon.
* NubileSavage: Cavegirl Mlor, the daughter of Shad and Gronk. She's a beautiful teenaged blonde, dressed in animal furs. This is in spite of living in a cave in One Million B.C., amongst a very primitive tribe. Astronauts Mac and Hec were both instantly smitten when they first met her in "And Then I Said Happy Birthday To You".
* TheresNoPlaceLikeHome: The astronauts, having been stranded in OneMillionBC, fix the Scorpio E-X-1 and get back to the future midway through the series ("Twentieth Century Here We Come"). However, they take their friends Shad, Gronk, Mlor and Breer with them, and HilarityEnsues as the cave family reacts to modern life.
* TimeTravel: A round trip for the astronauts, one way for Gronk, Shad, Mlor and Breer.
* TrappedInThePast, turning into GetBackToTheFuture when they fix their spacecraft.