Adam McKay says he and Christian Bale let their passion get the best of them!

The Big Short director talked to ET at the ACE Eddie Awards in Los Angeles, where he revealed that his spectacular impromptu lip-lock with Christian Bale -- after winning Best Comedy at the Critics' Choice Awards -- just sort of happened.

"Christian Bale is a very passionate actor. I'm a passionate director," McKay explained. "We also, you know, emotions flow and when we won the Critics’ Choice Award, we both looked at each other and said, 'This is happening.'"

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"And it didn't stop in that moment. It continued. In a cabana," the 47-year-old director joked with a laugh. "No, no, it stopped in that moment."

McKay further elaborated on the smooch during his acceptance speech, saying, "That’s collaborative love between Christian and I. Don’t judge it. It’s what fuels movies like this."

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Glad to have an eye into your process, Adam!

Watch the video below.