Sienna Miller had no romantic chemistry with Ben Affleck.

While looking back at her past male co-stars, Miller told “The Drew Barrymore Show” that things didn’t heat up between her and Affleck in “Live By Night”.

“Ben Affleck was like my brother [on set],” she said of the 2016 crime drama. “I’ve never laughed so much in my life. I mean, that sounds like a ridiculous thing to say and like a name-dropping thing to say, but I actually mean it.”

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“We had zero chemistry whatsoever. It was hysterical. We were supposed to be in love. We could not be less attracted to each other, which was hysterical,” she added. “He has an enormous head, I have a small one, so they’d have to like put me slightly ahead of him…and he directed the movie and I could barely look at him for laughing the whole time.”

Miller also doesn’t understand “casual dating” in North America.

“Like if you kiss someone in England, you’re basically together,” Miller explained. “Like this whole ‘I’m dating a few people’ thing, I’m like ‘what is happ… like, how does anyone even manage that?!'”

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“The Drew Barrymore Show” airs weekdays at 3 p.m. ET on Global.