8. Louise Lasser
Louise Lasser, an ex-wife of Woody Allen, was the first host banned by the producers (in 1967). Lasser was going through a difficult time in her personal life and had been arrested for drug possession just weeks before the show.
source: Parade
Lorne Michaels is said to have regretted the decision to invite her to host almost immediately, as she behaved erratically through rehearsal week (including crawling on her hands and knees into various Rockefeller Center offices looking for drugs).
Right before the show was about to begin, Lasser locked herself in her dressing room and refused to come out. Chevy Chase yelled to her through the door that he’d wear braids and perform her parts if necessary. She eventually emerged, but was nearly incoherent throughout the broadcast. She refused to appear in any sketches unless she was in them alone, or if her only costar was Chevy Chase. Needless to say, Lorne Michaels was not pleased, and banned Ms. Lasser immediately.
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