They say that couples eventually start to look like, and it seems like that's the case for Jennifer Aniston and her fiance Justin Theroux.

The engaged couple appeared at the 26th American Cinematheque Award Gala honoring Ben Stiller in Beverly Hills on Thursday, and the pair wore matching outfits for their walk on the red carpet.

Black and white was the theme of the evening for Aniston and Theroux. The 43-year-old actress wore a floor-length black gown with white detailing in the bodice, accessorizing with a white handbag and the enormous engagement ring she got from Theroux, which has been estimated to be worth half a million dollars. Theroux, 41, matched his lady love in a crisp and classic black and white tuxedo.

CLICK HERE to check out a series of photos of Aniston and Theroux on the red carpet for the 26th American Cinematheque Award Gala in Beverly Hills.

The couple was also recently spotted together enjoying a private and romantic dinner at the Madeo restaurant in Los Angeles. Maureen Klepfer, who dined at Madeo on the same night, talked with Celebuzz about the couple's meal and spotting Aniston's huge engagement ring, which she said looked "ginormous on her tiny hand."

"They were sitting with Chris [McMillan, Aniston's hairstylist] at a super-private corner booth which was dimly lit," Klepfer said. "They were all pretty quiet and mellow. Justin and Jen were both dressed casually - he was wearing all black and Jen was wearing baggy jeans. And Justin is really handsome in person. After they finished their meal they left quietly out a back entrance."

Aniston has been the subject of many pregnancy rumors over the last few weeks, including a recent report from Star Magazine, which her spokesperson vehemently denied.

"It's just another fabrication," her rep said. "She was just at LACMA and she certainly does not look pregnant. When has Star ever been right?"

Aniston certainly showed no signs of a baby bump when she attended an art gala at the Los Angeles County Museum of Art and wore a revealing Tom Ford gown with a plunging neckline. CLICK HERE to check out photos of Aniston showing off her body at the 2012 Art + Film event.