In a new Details cover story, Shia LaBeouf says he had a fling with his ‘Transformers’ co-star, Megan Fox.

“Look, you’re on the set for six months, with someone who’s rooting to be attracted to you, and you’re rooting to be attracted to them,” he said in the issue.

“I never understood the separation of work and life in that situation,” he said. “But the time I spent with Megan was our own thing, and I think you can see the chemistry onscreen.”

LaBeouf did not specify when the hook-up actually occurred, which led Details to ask: Was it while she was dating her now-husband, Brian Austin Green?

“I don’t know, man. I don’t know. I don’t know. I don’t know … ” he said. ” … It was what it was.”

Well, whatever happened, we can’t say we blame him.

[Details]