AMC's Mad Menstarts their final countdown on April 5, but the cast already said goodbye to the set after they wrapped shooting last year. ET got the scoop on the mood for their last day of filming.
"The last shot and set up -- we got it and said that's a wrap and I looked up and there were probably 300 people behind the thing and it was like, 'Oh yeah!' I forgot how big it was," Jon Hamm told ET.
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"It was just a lot of tears and a lot of champagne," January Jones said. "We just stayed there after we were done. We just stayed there. None of us wanted to go home. It was really sad."
For six and a half seasons fans have been captivated by the swoon-worthy Don Draper, but show creator Matthew Weiner said the part almost went to someone else.
"There was some questions about his sex appeal," Matthew told ET.
That concern is of course laughable now, as Jon quickly became a sex symbol for his iconic role as the successful advertising pitchman.
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"I'm forever grateful to Matthew, honestly, for sticking to the courage of his convictions and holding to his opinion," Jon said.
Elizabeth Moss was the first to audition for Peggy Olson, but she actually had competition from January for the role since her eventual character hadn't been written yet.
"There was no Betty, so I auditioned for Peggy," she said.
While the show made many stars, the fashion itself also played an important role, making Jon the perfect subject for GQ's latest cover. Inside the issue, Jon reveals that Breaking Bad star Bryan Cranston gave him advice on how to deal with Mad Men coming to an end.
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"It's hard, man. It's hard to let it go," Bryan told Jon. "It'll hit you a couple of different ways at different times."
There are only seven episodes of Mad Men left! The final countdown begins April 5.