The first cast member hired was Gilda Radner. The rest of the cast included fellow Second City alumni Dan Aykroyd and John Belushi, as well as National Lampoon "Lemmings" alumnus Chevy Chase (whose trademark became his usual falls and opening spiel that cued the show's opening), Jane Curtin, Laraine Newman, and Garrett Morris. The original head writer was Michael O'Donoghue, a writer at National Lampoon who had worked alongside several cast members while directing The National Lampoon Radio Hour. The original theme music was written by future Academy Award–winning composer Howard Shore, who – along with his band (occasionally billed as the "All Nurse Band" or "Band of Angels") – was the original band leader on the show. Paul Shaffer, who would go on to lead David Letterman's band on Late Night and then The Late Show, was also band leader in the early years. George Coe was hired because NBC wanted to have an older person in the cast.

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Much of the talent pool involved in the inaugural season was recruited from the National Lampoon Radio Hour, a nationally syndicated comedy series that often satirized current events.

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