The lyrics “Flintstones, meet the Flintstones” first appeared in season 3.
During the first two seasons of The Flintstones, the opening and closing credits used “Rise and Shine,” an instrumental theme accompanying Fred’s drive home from work. The vocal theme “Meet the Flintstones” replaced it beginning with season 3, episode 3, “Barney the Invisible.”
The song was composed by Hoyt Curtin and performed by the Randy Van Horne Singers with a 22-piece big band. Its melody is partly derived from the second movement of Beethoven’s Piano Sonata No. 17, composed in 1801–02.
A common source of confusion is syndication. “Meet the Flintstones” was later used for episodes from the first two seasons when they were rerun, so viewers who watched the show in syndication may remember the lyrics on episodes that originally opened with the instrumental theme. In the original broadcast sequence, however, the change belongs to season 3.