Longtime Saturday Night Live cast member Kenan Thompson recently revealed how Robin Williams was cast for a near-silent cameo during a classic sketch. During the 1970s, the Dead Poets Society star began his career in San Francisco, performing stand-up comedy and honing his legendary improvisational skills. His talents landed him a lead role on the television comedy series Mork & Mindy before moving on to theatrical hits including Good Morning Vietnam, The World According to Garp, and Good Will Hunting among many others.

While on the Fly on the Wall podcast with Saturday Night Live alums Dana Carvey and David Spade, Thompson recalled working with Williams on the popular “What Up with That?” sketch. After an unnamed cameo suddenly dropped out, Saturday Night Live creator Lorne Michaels suggested Thompson talk to Williams as a replacement. Read what Thompson said below:

“[The second seat of ‘What Up With That’] is usually just someone that really just sits there and doesn’t say anything at all. It’s like reserved for any kind of famous person that wants to be there or that we can get. [After someone dropped out, Lorne Michaels] was like, ‘You should ask Robin.’ 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—.’ I went and talked — I didn’t even finish my sentence — he was just like, ‘Absolutely.’ He was just an angel. That was crazy.”

Why What Up with That? Was So Popular on Saturday Night Live

Developed by Thompson alongside former head writer Bryan Tucker and writer Rob Klein, “What Up with That?” centers on Diondre Cole (Thompson), a talk show host who is obsessed with his own theme song. After a boisterous opening number featuring backup singers Pippa and Poppy, Cole attempts to interview a celebrity guest but repeatedly interrupts any answers by revisiting the song. As a result, the show would run out of time without the celebrity guest finishing their interview. A second guest would generally remain silent for the sketches duration and the regular third guest, Bill Hader as Fleetwood Mac guitarist Lindsey Buckingham, would complete the sketch without uttering a single word.

Each music break features additional wacky recurring characters including Ted Lasso star Jason Sudeikis as a permed track-suit-wearing backup dancer as well as Wednesday star Fred Armisen as a smooth jazz saxophone player named Giuseppe. The second musical break would last longer than the first and would generally include more cast members in outlandish appearances as seemingly random characters, keeping the sketch fresh for each iteration. Abby Elliott slid across the stage in a prop well as an adult Baby Jessica, Bobby Moynihan danced a jig as WWF legend Jake the Snake, and Brooklyn Nine-Nine star Andy Samberg flew into the number as Godzilla’s on-again-off-again adversary Mothra.

Thompson starred as Cole for 12 episodes including the 40th Anniversary Special and a COVID-19 edition of the variety show shot at the cast members’ homes. In an era where recurring characters have fallen out of favor due to ease of access of past sketches on NBC’s website and YouTube, “What Up with That?” managed to persevere for over a decade with great success. Providing audiences with legendary live moments including Samuel L. Jackson’s prolific F-bomb, perhaps Thompson will revisit the sketch one more time before he retires from Saturday Night Live as the longest-serving cast member.