How Robin Williams ended up in a Saturday Night Live sketch where he hardly says a word

Kenan Thompson is pulling back the curtain on how he got Robin Williams to play a tiny role in one of his Saturday Night Live sketches in 2010.

The actor, who has starred on the sketch comedy series since 2003, revealed that Lorne Michaels once told him to ask Williams to appear in his recurring segment "What Up With That" after an unnamed celebrity dropped out. In the sketch, Thompson hosts a chat show but stops his guests from ever actually speaking by frequently breaking out into song and dance.

As a result, Thompson explained on Wednesday's episode of Fly on the Wall with Dana Carvey and David Spade that second seat in the sketch's lineup — where Williams was sitting — is "usually just someone that really just sits there and doesn't say anything at all." He added, "It's like reserved for any kind of famous person that wants to be there or that we can get."

At the time, Thompson noted that Williams happend to be "just around," which prompted Michaels to suggest that he recruit the Mrs. Doubtfire actor for the skit.

"He was like, 'You should ask Robin,'" he said. "I was like, 'I should ask Robin? I should just go ask Robin Williams to just sit in my sketch and not say a word? Like, seriously?' And he was like, 'Yeah.' I was like, 'S---.'"

But Thompson need not worry, because Williams instantly accepted the role. "I went and talked — I didn't even finish my sentence — he was just like, 'Absolutely,'" he said. "He was just an angel. That was crazy."

In the sketch, Williams stars as himself alongside fellow actor Robert De Niro and Lindsey Buckingham (played by Bill Hader). After making a silent introduction, Williams only chimes in a handful of times in between Thompson and Kristen Wiig's hilarious performances.

At the end, Williams can be seen typing away on his phone while De Niro peers over his shoulder. He later jokes, "I'm just tweeting what a great time I didn't have."

Listen to Thompson talk about the sketch in the podcast above.

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