SNL episodes are hard, often frenzied work, so you can imagine the sort of time and dedication and stress that went into the SNL 40 show, which featured new and former cast members along with several guest stars. One of the highlights of the three and a half hour event was the return of “Celebrity Jeopardy!” with Norm MacDonald, Will Ferrell and Darrell Hammond reprising their iconic sketch roles alongside fellow SNL stars, including Kenan Thompson doing a hilarious (and timely) Bill Cosby impression. But according to MacDonald, Thompson wasn’t originally supposed to be in the sketch: Eddie Murphy was.

MacDonald took to Twitter to tell a long and incredible story about his week back at SNL, where he worked hard with his “Celebrity Jeopardy!” co-writer Steve Higgins and Lori Jo Hoekstra to write the new sketch for the 40th anniversary show. MacDonald describes the genesis and intention of the sketch, and why it’s been such a classic for so many years. And while he expresses disappointment with Lorne Michaels’ insistence on adding several more impressions to the sketch, he was rather taken with the idea of including the Bill Cosby “Video Daily Double” bit, which ultimately saw Kenan Thompson donning the colorful sweater.

As you might already know, Norm MacDonald and Lorne Michaels have had some issues in the past, but MacDonald addresses that pleasantly before getting into his story. Apparently Thompson wasn’t supposed to play Bill Cosby. Norm MacDonald wanted Eddie Murphy, and it was his job to try and get him to do the bit, which Murphy ultimately passed on.

Admittedly, the Bill Cosby rape allegations are incredibly controversial, and not every star is happy to jump in and mock the comedian. (Tina Fey and Amy Poehler did it beautifully at the Golden Globes, though.) At any rate, Murphy decides not to do the Cosby thing for the sketch, and that’s the gist of MacDonald’s story.

But there’s a lot more, too, like MacDonald explaining why he respects Mike Myers (and insanely referring to his films as “perfect”), an anecdote involving Paul McCartney and referring to Sarah Palin as “irresistible.” It’s truly one of the greatest twitt

You can read (most of) MacDonald’s story below, or head over to Twitter to read the entire, impressive thing in full.

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