Some Saturday Night Live sketches leave viewers wondering, ‘How did they come up with that?’

The inspiration for others, however, is pretty obvious – like when John Belushi opened the show on Jan. 22, 1977, in a wheelchair.

At the time, Belushi was SNL’s biggest star. Chevy Chase had departed the series a few months prior and new arrival Bill Murray was yet to establish himself among the show’s top talents. Meanwhile, Belushi was the program’s wild man, known for his antics both on screen and off.

Drug use was rampant, even on the set: “There were cocaine lines the length of a desk,” comedian Robert Klein said in the book Live From New York: The Complete, Uncensored History of Saturday Night Live. “Most people could handle it, but a few people fell very badly through the cracks.”

Belushi was arguably the heaviest user of the bunch, regularly partying so hard that his health suffered as a result. But somehow he never let addiction stop him from taking the stage.

“We did this one sketch about fishing in Alaska, and right before we went onstage I was in the back of the set with John and he was green – just green,” castmate Laraine Newman said in Live From New York. “I knew he would go on. I just didn’t know how long he was going to live.”

Belushi was also known to play up his health issues, especially in front of the show’s celebrity guests.

“The better an actor the host was, the sicker Belushi would be,” Murray said in Live From New York. “He would be hours late and at death’s door, and he would come in a robe unable to speak. He’d have doctors in his dressing room. It would be just incredible. And the host would be thinking, 'Belushi isn’t even going to show up, he's too sick to even work' – and then John would come out on the show and just blast them away.”

These drug-induced illnesses had become common knowledge behind the scenes. In 1977, they were put on camera.

The sketch began with SNL creator Lorne Michaels talking into a telephone, explaining why Belushi would not be able to appear in that night’s episode. “You’re gonna have to ask Danny [Aykroyd] to go ahead and do the opening,” Michaels said. “Belushi is just not ready.”

At this point, Belushi’s “doctor” entered the room and begged for his patient to be allowed on television. Belushi would then be wheeled in, appearing half-conscious and writhing in his chair.

“Lorne, if John Belushi could speak, he’d tell you he’s got to go on,” the doctor declared. There was, of course, a reason for the his pleas: “If [Belushi] doesn’t go on, he doesn’t get paid. And if he doesn’t get paid, I don’t get paid. And if I don’t get paid, I’ll be forced to cut off his drugs.”

The last line prompted Belushi to spring up in his chair, suddenly clear headed and ready to perform. "Live from New York," he declared, "it's Saturday night!"

Though Belushi's demons were played for laughs on the show, they eventually caught up to him. Belushi died of a drug overdose in 1982.

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