Jessica Chastain, Boyfriend Gian Luca Passi de Preposulo Getting Serious

Jessica Chastain and Gian Luca de Preposulo Paul Archuleta/FilmMagic; Pier Marco Tacca/Getty Images

Zero dark sexy! Jessica Chastain recently told Us Weekly she'll be attending this Sunday's Academy Awards with her grandmother — but that doesn't mean the actress, 35, doesn't have a special man in her life.

The redheaded Zero Dark Thirty star, 35, has been quietly seeing Gian Luca Passi, an Italian-born executive for French fashion brand Moncler. "They've been dating seriously for awhile now and Gian really likes her," a source tells Us. The twosome have made a pact to keep their relationship out of the spotlight. "He is a classy guy and completely agrees about respecting their relationship and not flaunting it," says the source of her man, recently seen taking in a performance of her Broadway show The Heiress.

Chastain spoke discreetly about her man during a recent appearance on Katie. When Katie Couric asked Chastain if she had a boyfriend, she demurred, "I do . . . I have a rule that I don't date actors so he's not in the business at all . . . He's in the fashion industry."

And on at last weekend's Writers' Guild Awards in L.A., Chastain — up against Jennifer Lawrence, Emmanuelle Riva, Naomi Watts and Quvenzhane Wallis in the Best Actress category at this Sunday's Oscars — couldn't help but gush a bit about her man at a backstage gifting suite.

Picking up a bottle of Purity Vodka, Chastain cooed, "My boyfriend loves Vodka. The bottle is pretty."

Still, her hunk won't be by her side come Sunday. That'll be Chastain's grandmother. "Going with her, it's such a reminder to enjoy it," the Mama star told Us Weekly recently.

With that in mind, she stopped by the Kari Feinstein Style Lounge at the W Hollywood Hotel on Thursday. "She was so excited to grab electronic cigarettes from e-Puffer," an observer reveals of the second-time nominee who also swooped up dry shampoo from Dove and Nalukai Jewelry. "But she is trying to help her grandmother quit!"

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