Mark Waters shares with EW the untold story of how the iconic “stripper thigh slap” was born.

“They were going to turn and stick their posteriors up in the air,” Waters says.

Go with something else.'"

MEAN GIRLS, Lacey Chabert, Rachel McAdams, Lindsay Lohan, Amanda Seyfried, 2004, (c) Paramount/court

The cast of ‘Mean Girls’.Everett Collection

It was in later choreography rehearsals for the dance that the now-infamous “thigh slap” was born.

“And Neil Flynn’s reaction shot!”

“We hired a choreographer; it was going to be a much more elaborate dance.

That worked for the movie.”

Making matters even more complicated?

“You’d be surprised how hard it is to license Christmas songs,” Waters says.

We were just happy to have anybody say yes."

Call it a Christmas miracle that’s just sofetch.

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