The Desperate Housewives star and Django Unchained actor held hands as they smiled for the cameras, and Jamie even wrapped his arms around the stunning brunette's waist.
Eva, 46, looked as gorgeous as ever in a strapless burgundy Marchesa gown featuring a sparkly bust-line teamed with a sequinned floral clutch bag, also by Marchesa, and pointed black stilettos.
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She wore her glossy tresses – to which she'd added dark blonde extensions for the occasion – in loose, relaxed curls and went for a pretty pink look with her make-up.
Her companion and old friend looked dashing in an all-black suit, tie and shirt.
Later, Jamie took to Twitter: "Just finished the red carpet for Project Imagination now time for the show. #CanonPI10 #AndSheWasMyEve."
The handsome duo – who denied suggestions of a romance back in 2006 – served as celebrity directors of Out of the Blue and ...And She Was My Eve for the festival.
The pair are currently both single. Eva recently split from her boyfriend of four months Ernesto Arugello, who she met producing reality dating show Ready for Love, on which he featured as one of the bachelors.
She is said to have broken things off with Ernesto, 34, because of their hectic timetables and geographical distance – Eva spends most of her time in Los Angeles while Ernesto is based in Miami.
Ray star Jamie, meanwhile, denied reports that he his dating Katie Holmes earlier this month.
"(The rumours) are 100 per cent not true," the 45-year-old actor told Entertainment Tonight.
"In fact it's quite hilarious because we simply danced at a charity event along with a lot of other people."