'I Didn't Steal Your Boyfriend' singer Ashlee wowed in an elegant strapless floor-length black gown with a ruffled hem at the Nokia Theatre screening on Monday evening (18 November).
Her bouncy blonde hair was arranged in curls over her shoulder, while beauty-wise she stayed true to her rock chick edge with a sultry smoky eyes and glossy black manicure.
Evan, meanwhile, who is the son of legendary singer Diana Ross, showed off his quirky style in black trousers, a leather waistcoat and red jacket.
The actor has landed a role in the next Hunger Games movie Mockingjay. He'll play Messalla, a member of a TV crew who follow Katniss (Jennifer Lawrence) around on a propaganda mission.
Ashlee and Evan cuddled up together on the red carpet and later, the loved up duo were seen holding hands as they left the screening.
Their red carpet appearance came after they spent the weekend celebrating Ashlee's son Bronx's fifth birthday in Studio City, California.
Ash's big sister Jessica was in attendance with her kids Maxwell and Ace, and fiancé Eric Johnson, as was Ashlee's ex-husband Pete Wentz and his new girlfriend Meagan Camper.
Pete recently told E! News that despite divorcing, he and Ashlee have a fantastic relationship and Bronx is their number one priority.
"I think the whole idea is you don't parent for the media, you parent for the kid," he said. "And I think the most important thing is putting your kid first. None of it is ever for show and a lot of it goes on behind closed doors, but yeah, yeah we respect each other as parents and that's the most important thing."
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