Hayden Panettiere, Stephen Colletti Check Out Shrek The Third, Grope Each Other

Hot-bodied jailbait princess Hayden Panettiere of Heroes and her beau, Stephen Colletti of Laguna Beach fame, were caught hand-in-hand heading to a matinee Monday.

Inside, they got closer still.

The twosome was spotted at The Grove cinema in L.A., where they locked lips and couldn't keep their hands off each other throughout a daytime screening of Shrek The Third.

That's right, PDA at a kiddie flick. The regulators had better bump up the rating to PG-13 at this particular theater. Some material may not be suitable for children!

This is just how Stephen Colletti rolls. Hey, the guy has dated Kristin Cavallari and Lauren Conrad … simultaneously. We're not about to question the man's game.

Hayden Panettiere was wearing a solid band on her engagement ring finger. Is Mr. Colletti ready to pop the question? Is there a lifetime commitment on the way for these two?

Hayden's BFF, Rumer Willis, was not available for comment. But think about it. Hayden can legally walk down the aisle when she turns 18 … in like 86 more days and 9 hours.