Leighton Meester and Adam Brody are engaged!

The Gossip Girl beauty accepted The O.C. hunk's surprise proposal, Star magazine reports.

"Leighton and Adam are crazy about each other and have talked about getting married eventually," an insider told the magazine.

"But she had no idea when he would propose so soon! It was the surprise of her life and she’s ecstatic!"

As Breaking Celebrity News previously reported, the couple got "close and friendly" while shooting 2011's The Oranges together and have been dating for at least 10 months.

Previous to Meester, 27, Brody, 33, was linked to director Lorene Scafaria in 2010 and famously dated hisO.C. co-star, Rachel Bilson, for three years.

Meester broke up with actor Aaron Himelstein late last year.

"Right now their plan is to get married next summer," the insider told Star.

"They are still deciding if they want a destination wedding or if they’ll marry in southern California somewhere."

Breaking Celebrity News reached out to reps for both actors but got no response at the time of publication.