There were plenty of loud laughs when Kristen Wiig played a wacky game of Mad Libs with a mustachioed Jimmy Fallon

Kristen Wiig appeared on Wednesday evening’s episode of “The Tonight Show” to promote her new movie “Despicable Me 3” and ended up putting on a doctor’s outfit for a particularly wacky Mad Lib Theater sketch with host Jimmy Fallon.

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While chatting to Fallon on the couch, Wiig came up with a series of words as you would for a regular game of Mad Libs, but this was no regular game of Mad Libs and instead of just reading the results allowed, Fallon and Wiig acted the script out in a dramatic medical-themed scene. Wiig played Dr. Mackerel, who diagnosed Fallon’s Mr. Gooby Gock with fluffy platypus disease.

Both participants giggled uncontrollably throughout the segment, especially when Wiig put on her fake spectacles and read off the side effects for Mr. Gock’s medication. “Side effects also include an itchy armpit and a decrease in the desire to hammer,” she said.