Shia LaBeouf Admits to Hooking Up With Megan Fox

"I think you can see the chemistry onscreen," LaBeouf tells Details of his scenes with Fox. - Tim Whitby/Getty …"I'm a little territorial and defensive," he says. "I don't like having my space invaded. - Matthias Vriens-Mc …If Megan Fox is a little peeved at Shia LaBeouf rightnow, it's tough to blame her. LaBeouf, her co-star from the first two"Transformers" installments, has been pretty loose-lipped lately,telling the media earlier this month that the 25-year-old hottie couldn'thandle her sex symbol status, beforerevealing that she got fired from the action franchise for talking you-know-what. Now, just in time for the release of "Transformers 3"[The attractive young female role is now being played by lingerie model RosieHuntington-Whiteley for this one], LaBeouf tells Detailsthat he and Fox indeed hooked up when they were shooting together.

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"Look, you're on the set for six months, withsomeone who's rooting to be attracted to you, and you're rooting to beattracted to them," he says in the magazine's August issue. "I neverunderstood the separation of work and life in that situation. But the time Ispent with Megan was our own thing, and I think you can see the chemistryonscreen."

But wasn't she dating her now-husband Brian Austin Greenback then? "I don't know, man. I don't know." After 10 more "Idon't knows," LaBeouf simply states: "It was what it was."Expect things to be a little awkward in the Fox-Green household for a while.

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The 25-year-old says his one date with Hilary Duff was "probably the worst date either of us have ever had." - …

Fox isn't his only victim. LaBeouf also takes aim atHilary Duff, saying his one sushi dinner with the actress-singer was "probably the worst date either of us have ever had."

His "Wall Street" co-star, Carey Mulligan, whohe dated for about a year, gets off easy. "I still love her," saysthe 25-year-old. "I think she's an awesome person and an incredibleactress. We're still pals. I wouldn't take any of it back, and I don't thinkshe would either. It just ran its course."

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When it comes to Mr. Honesty turning his analysis onhimself, he freely admits in the interview he can lose his cool quite easily, aflaw that stems from growing up in a tough L.A. neighborhood where he had todefend himself at school on a daily basis. Case in point: the fight he got intoat a bar in February after refusing to take a photo with an eager"fan" that ended with LaBeouf in handcuffs ... and in headlines.

Shia LaBeouf appears on the cover of the August issue of Details . - Matthias Vriens-McGrath

"I would like to be George Clooney diplomatic,"he explains. "I just don't have the wherewithal yet or the inner serenity.My [bull] meter is tuned very sensitive."

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As for when a paparazzo aimed his camera at the window ofLaBeouf's house, prompting the actor to storm outside, grab the photog'sequipment and hold it hostage until police arrived, again, LaBeouf concedeshe's not perfect.

"I'm a little territorial and defensive," hesays. "I don't like having my space invaded. I'm a human being who payshis taxes. And I don't respond in a really sweetheart way. I mean, maybe Ishould develop that, but even as I say that, I have this cheerleader in theback of my head that's like, 'No, man, don't conform!'"

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