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

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

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

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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.