Megan Fox, Jason Segel, Chris O'Dowd In A Pool (PHOTO)

Megan Fox is diving right in to comedy, so to speak.

The ex-"Transformers" star is making the most of her small role in Judd Apatow's upcoming film, the tentatively titled "This Is 40," which revolves around Paul Rudd and Leslie Mann's characters from "Knocked Up." Already, she's received praise from her co-star, with Mann telling MTV, "Megan Fox is so funny. She's hilarious. You wouldn't, I don't know if other people [expect it], but I think she's really funny, you'll be pleasantly surprised."

She's also getting close with her co-stars off the set, as evidenced by this pool shot she posted on her Facebook page on Saturday.

"On set of THIS IS 40 with Jason and Chris...Two very handsome, very tall, VERY funny men," she wrote.

Jason Segel and Chris O'Dowd, it should be noted, were all smiles.