The modern Stone Age family meets the family of the future when a time machine brings together the Flintstones and the Jetsons! It's the most incredibly hilarious get-together of all time when Elroy's latest science project, a time machine, transports the Jetsons back to the 25th century B.C., where they make fast friends with Fred, Wilma, Barney and Betty. Then, in an outrageous switcheroo, the Flintstones and Rubbles are accidentally zapped far into the future. As George is getting rich with his anti-gravity boots, the Flintstones are busy becoming America's first family. But when the Jetsons go back to the future, the time machine breaks! Will the Flintstones ever get back to Bedrock?