FX’s It’s Always Sunny in Philadelphia added Danny DeVito to the main cast in its second season after the show’s producer suggested that the Gang get a famous actor into the series. The gamble played out well as DeVito loved the series and blended in perfectly with the weird, dark humor of the sitcom.

While DeVito is known for being a great worker on set, the Batman Returns star reportedly scared co-star Mary Elizabeth Willis, who played The Waitress in the show. The actress mentioned that when she approached him on day one of filming, he did some nasty things to get into character, which initially put her off.

It’s Always Sunny in Philadelphia star did not want to work with Danny DeVito after the first day Danny DeVito in It’s Always Sunny in Philadelphia | Credits: FX

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