Hanna-Barbera hadn't quite given up on pre-fab bubblegum pop by 1973, even though Josie & the Pussycats in Outer Space was in perpetual rerun for its 2nd & final season on CBS, and the band made a visit to the Scooby-Doo Movies. NBC wanted back in, and H-B served up Butch Cassidy and his band, the Sundance Kids, who doubled as secret agents. Their "boss" was a sentient computer, Mr. Socrates (voiced by H-B regular John Stephenson), who had an odd affliction----an allergic reaction to the band's dog, Elvis. Ex-Monkee Micky Dolenz lent his voice to the band's drummer, Wally (who happened to be Elvis' owner). Butch and the band fought the usual assortment of garden variety would-be dictators and such, just as Josie did 3 years earlier, but unlike the Pussycats, the Sundance Kids drifted into the sunset after 1 season.
Pterixa uploaded this sample from the show to YouTube. In this scene, the Sundance Kids perform "Lookin' For Someone":
A revival of the series would be nice, but this time it'd have to have a harder edge and some much needed continuity in order to appeal to today's audience. Whaddya say, WB?