Who Jon Hamm Told About the Secret Ending of 'Mad Men'

"She won't tell anyone!" he added.

ByABC News
September 22, 2014, 4:11 PM
Don Draper in a scene from the seventh season of "Mad Men."
Don Draper in a scene from the seventh season of "Mad Men."
Frank Ockenfels III/AMC

— -- Secret endings to epic TV shows that are revealed in the house stay in the house.

"Mad Men" star Jon Hamm recently dished to US Weekly that the one person in his life that he told about the ending to the AMC show that has captivated audiences for the past seven years is none other than his girlfriend Jennifer Westfeldt.

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"Oh, she knows," Hamm, 43, told the magazine last week.

"I tell her everything!" he said of his lady love since 1997. "I tell her everything and she definitely knows."

But if you think you'll get the ending to "Mad Men" from Westfeldt, you're sorely mistaken.

"She won't tell anyone!" he added.