Stacy Keibler and George Clooney, at Paris premiere of The Descendants
Pascal Le Segretain/Getty Images
10/19/2011 at 08:00 AM EDT
It's hard to top a red-carpet premiere on the Champs-Elysées for glamour. But how about introducing your date afterward to two legendary French actresses by the light of the Arc de Triomphe?
made it a night to remember for Stacy Keibler in Paris on Tuesday. With his new movie The Ides of March
opening across Europe, the couple first hit the red carpet together in a rainstorm, with Clooney making sure Keibler was safely inside before he mingled with the crowds.
"She came with him, and he watched her step out from the car. She is amazing to look at in a long strapless grey gown. She is incredibly beautiful," one onlooker told PEOPLE.
After the movie, they slipped back to their Place Vendome hotel before heading to the afterparty at L'Arc, a 19th-century townhouse mansion at the top of the Champs-Elysées that's been converted into a nightclub/restaurant with dramatic views of the Arc de Triomphe.
"They came around 11:30," says one invitee, "and stayed until well past 2:30 in the morning. They hugged some together, but weren't what you would call very kissy-kissy in public. [But] he is remarkably attentive towards her."
The source adds: "He seems very smitten. And she seemed very impressed by the evening."
Joining the couple for dinner were renowned French actresses Catherine Deneuve and Juliette Binoche. "Stacy sat on George's right, Catherine Deneuve on his left. Juliette was on the other side," L'Arc's Gregory Lentz tells PEOPLE.
Rounding out the table were Clooney's Ides
co-star Phillip Seymour Hoffman and a pair of princesses – Charlotte Casiraghi, a Monaco royal, and the actress Clotilde Courau, Princess of Venice and Piedmont.
The evening menu included fresh pasta served with tomatoes and basil, grilled sole and a large red fruitcake which centerpieced the table with sparklers. "George drank mostly red Burgundy and there was a toast of Moet & Chandon champagne," says Lentz.
Clooney and Keibler "stayed late and spoke to everyone," he adds.
Next up, the actor headed to London on Wednesday, where he appeared at a press event for the London Film Festival.