New film Saturday Night celebrates the legendary comedy show's origins – but last weekend's poor new season premiere confirmed it's on rockier ground than ever. What went wrong?

Shuster is the show’s serenely funny Mother Courage, confident that even if the whole thing goes up in flames, they were right all along, and that American television in 1975 was an aging anachronism badly in need of a defibrillator.

With a new film about the show, and a 50th anniversary season starting, Chevy Chase, Garrett Morris, Jane Curtin, Laraine Newman and others look back.