On Thursday, the birthday boy invited Crystal on The Tonight Show to flip lips. With a little help from the TV control booth, Fallon and the When Harry Met Sally actor switched mouths and took turns speaking for one another.
"I just bought a Tesla. It makes no sound," Crystal's lips said while pasted onto Fallon's face.
This isn't the first time the host has relied on this goofy switcheroo. Fallon and Crystal pulled the same trick on his previous show, Late Night with Jimmy Fallon.
Watch Crystal and Fallon's full exchange with their new mouthpieces below.
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