Shia LaBeouf admitted there was more than meets the eye between him and Megan Fox while filming the "Transformers" movies -- and told Details magazine the two hooked-up off-set!

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

While we haven't heard Megan's side of the story yet, a ton of celebrity hook-ups started on the set -- including Brad Pitt and Angelina Jolie, Blake Lively and Penn Badgley, Ryan Gosling & Rachel McAdams and many more.

Check out the gallery above to see who else have made their on-screen romances an off-screen reality!

Fore more Shia, check back at today around 2:30pm PT -- where we'll be live streaming the NY premiere of "Transformers: Dark of the Moon."

Maybe they'll ask him about Megan!