Leighton Meester, Boyfriend Adam Brody Costarring in Life Partners

Real-life couple Adam Brody and Leighton Meester are set to star together in the upcoming comedy Life Partners. Henry S. Dziekan III/WireImage.com

Leighton Meester and Adam Brody just can't seem to get enough of each other. The couple, who already spend plenty of time together in real life, are now set to share some time onscreen, as costars in the upcoming comedy Life Partners, Deadline reports.

The two obviously have chemistry, but don't expect any romantic sparks to fly between them in the movie. Helmed by first-time director Susanna Fogel (who also co-wrote the screenplay), the film is about a girl named Paige (played by Community's Gillian Jacobs), who vows not to get married until her lesbian friend Sasha (Meester) has the same legal right. Brody plays Tim, a charming doctor who throws a wrench into those plans by sweeping Paige off her feet. (The movie also features performances by Gabourey Sidibe and Abby Elliott.)

Life Partners actually marks Meester and Brody's second film together. The actors — both veterans of teen TV shows — first appeared as costars in the 2011 dramedy The Oranges, alongside Catherine Keener and Hugh Laurie.

Us Weekly first broke the news that the two had been secretly dating for weeks back in February. "They were always close and friendly," a source told Us at the time, noting that the O.C. alum, 33, and the Gossip Girl star, 27, would "hang out" occasionally while they were shooting The Oranges.

"They're a really cute couple," another insider said. "They've been circling around in similar circles for years."

Brody previously romanced his O.C. costar Rachel Bilson until 2006 and has also been linked to director Lorene Scafaria in recent years. Meester, meanwhile, has dated actors Aaron Himelstein and Sebastian Stan.

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