Mad Men Alum John Slattery Says Jon Hamm's Good Looks Distracted People on Set: They 'Would Just Go Catatonic'

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People apparently stopped in their tracks upon seeing Jon Hamm proved to be dressed as his Mad Men character Don Draper.

According to his former costar John Slattery, Hamm easily grabbed the attention of cast members on the set of the Emmy-winning series, which aired from 2007 to 2015.

"When Hamm walked into a room in that get-up, people would just go catatonic," the 60-year-old actor, who played Roger Sterling, told The Independent. "Guest stars would sometimes walk up to him and their lines would go right out of their heads."

Slattery added, "They just wouldn't know what to do. It happened on more than one occasion."

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Back in 2014, Hamm, 51, shared that he didn't understand the fascination with Don Draper, calling him "a terrible guy."

"With men, it's like, 'That's the guy you want to be?' Go buy a nice suit and comb your hair, but don't do the other parts of the character," he told Glamour at the time. "And I find it crazy when women like Don. There are better dudes. You wanna date smart, good-looking, talented Ken Cosgrove. That's who you want to be with."

Hamm was not the only one to turn heads on the set of the hit AMC drama. According to Slattery, "Christina Hendricks would walk into the room and people would s--- themselves — it was amazing."

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Slattery — who recently reunited with Hamm on the film Confess, Fletch — said he received attention when dressed in the show's 1960s attire, too.

"Well… we were all sort of curated," he explained. "The look of it. I'm not being false humble, either. In that get-up, I certainly looked different to how I do walking around every day."

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Slattery, in fact, initially auditioned for Don Draper before producers told him that the part was going to Hamm.

"They said, 'Here's the thing – we have this guy,'" he also recalled to The Independent. "[Hamm] claims I was in a bad mood the whole time we shot the first episode because of this, but I don't think that's true."

Slattery added, "Eventually I saw him, and I was like… 'Oh – they sure do have that guy'."