Jon Hamm Recalls Consuming Fake Cigarettes and Martinis While Filming ‘Mad Men’

Martinis and cigarettes might have made for a perfect 1960s aesthetic on the Mad Men set, but they didn’t give the cast the best breath.

Jon Hamm reunited with his former costar John Slattery on Saturday, May 31, for a Mad Men panel at the ATX TV Festival, and the pair reflected on their eight-year run on the hit series — and all the fake smoking they had to do during that time.

“I think somebody did a count, and in the pilot alone, I smoke 75 cigarettes,” Hamm, 54, said during the panel. “They are fake cigarettes, but that just means that there’s no nicotine in them. It doesn’t mean you’re not burning something.”

It didn’t help that they filmed the New York City-based show in Los Angeles, so they were always inside on sets. “We didn’t go outside, which was awesome and not awesome,” Hamm said, as it meant the “whole stage [was] full of fake cigarette smoke.”

The martinis Hamm drank as Don Draper alongside his castmates piled on, too. “Oh, the breath was lovely,” he quipped, after Slattery revealed what the fake martinis were made of.

“Pop another pearl onion in your glass of water, and then smoke 26 more fake cigarettes and it’s 9:30 in the morning!” Slattery, 62, joked.

There were so many replicated substances being imbibed on camera that Hamm recalled the network asking if the cast really had to smoke in scenes.

“And we said, ‘Are you kidding me? Yes, they have to smoke,'” he said. “We had to lean into the good and the bad and the ugly of it.”

In the decade since Mad Men’s finale aired, the friendship between Hamm and Slattery has only continued to grow.

“You could grow to hate each other or grow to love one another,” Hamm told PEOPLE of working so closely with someone for so many years. “We became great friends.” 

“When we’re hanging out together — on the beach, in the city, out in L.A. — it’s truly a gift,” he said. “When we also get to extend that into working together, that’s icing on the cake.” 

Slattery echoed that, and told PEOPLE how his perspective on friendships has changed with time.

“The older I get, the more I’m aware of the passage of time. Knowing this whole thing is finite and there’s a winnowing list of people with whom you want to spend your life. I just enjoy Jon’s company. I value it.”

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All seven seasons of Mad Men can be streamed on AMC+.