In the vast pantheon of T.V. sitcom characters, Charlie Kelly has long existed as one of America’s most beloved social miscreants. Over the course of It’s Always Sunny in Philadelphia’s 12 seasons on FX, the Paddy’s Pub janitor has eaten everything from milksteaks and erasers to canned cat food and maggot-ridden raccoon meat—all while huffing glue, pounding beers, and committing a slew of felonies in the process.

Still, no matter how many outrageous foodstuffs Charlie Kelly has consumed on screen, nothing could prepare actor Charlie Day for the capsaicin-fueled gauntlet that is the Hot Ones challenge.

Outside the city limits of Philadelphia, Day is surprisingly calm, cool, and collected, joining host Sean Evans in Los Angeles to promote his new film, Fist Fight, with Ice Cube. But like Dr. Jekyll and Mr. Hyde, some 550,000 Scoville units slowly transform the suave, Hollywood actor into the high-pitched lunatic we’ve all come to know and love.

Watch the video above to see how far up Mount Scoville Day climbs while dishing on Tracy Morgan, Wade Boggs, and the City of Brotherly Love.

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