While at the World's Fair, the Flintstones and the Rubbles laughingly step into a time machine, which they believe to be a hoax. But before long, they are transported to Ancient (but to them, future) Rome, Arthurian England, on board the ship of Christopher Columbus, and to Colonial America to meet Ben Franklin.
Elenco: Mel Blanc , Alan Reed , Jean Vander Pyl , Bea Benaderet , John Stephenson , Daws Butler , Gerry Johnson , Don Messick , Hal Smith , Howard Morris , Doug Young , Henry Corden , Harvey Korman , Allan Melvin , Jerry Mann , Don Messick .