The genesis for the “Joliet” brothers Jake (John Belushi) and Elwood Blues (Dan Aykroyd) was a 1976 Saturday Night Live skit where the actors played blues men with the fictional “Howard Shore and his All-Bee Band” group. Wearing costumes from a previous bee sketch, they sang the Slim Harpo song “I’m a King Bee,” with Belushi singing and Aykroyd accompanying him on the harmonica. The sketch launched both men’s interest in blues, and for several years by different routes both came to explore it. Their fascination after a while gave them the idea to develop a whole film about the blues, but first they had to flesh out their characters.

On this day, April 22, Belushi and Aykroyd introduced the Blues Brothers for the first time, in another Saturday Night Live skit that had them backed up by a full blues band, with some notable names in the genre, singing a cover of the blues singer legends Sam & Dave’s “Soul Man.”

Belushi and Aykroyd revived an interest in blues when they premiered their now immortal musician alter egos. The Blues Brothers film premiered in 1980 and featured musical cameos by Aretha Franklin, James Brown, Cab Calloway, Ray Charles and John Lee Hooker. It was the 10th largest-grossing film in the entire decade. In late 2011 the duo announced they are considering bringing back the characters — in which case, they might revive interest in blues for a second time.