Jon Hamm: Jennifer Westfeldt Knows the Secret Ending to Mad Men

Jon Hamm and Jennifer Westfeldt
Jon Hamm told Jennifer Westfeldt the ending to Mad Men. Dimitrios Kambouris/Getty Images

No secrets in this relationship! The highly anticipated series finale to Mad Men has been kept a secret for months, but Jon Hamm couldn't help but let the details slip to his longtime girlfriend Jennifer Westfeldt.

"Oh, she knows," Hamm, 43, told Us Weekly exclusively at CAA's School Day Benefiting Communities in Schools.  

"I tell her everything!" the Mad Men star continued of Westfeldt, 44. "I tell her everything and she definitely knows."

Hamm trusts his girlfriend of 15 years to keep mum on the show secret. "She won't tell anyone!" he added to Us.

The second half of the seventh and final season of Mad Men debuts in 2015, with the Emmy-winning show wrapping just months later. 

In the break between the two parts of the last season, speculation and rumors have been rampant, but Hamm maintained he hasn't been broadcasting the plot lines. 

"I'm pretty good at keeping it secret by now," he told Us. "I'm looking forward to it, I think we'll have a good time."

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