She's So Fancy! Warren Beatty and Annette Bening's Daughter Steps Out at Debutante Ball

Warren Beatty and Annette Bening's daughter Isabel is officially high society.

The 17-year-old was formally presented as a debutante at le Bal des Débutantes at the Palais de Chaillot in Paris on Saturday. Her Academy Award-nominated mother accompanied her to the event over the holiday weekend.

So what exactly was required of the Hollywood spawn at the ball, which Forbes magazine has described as one of the "top 10 social events in the world?" The niece of Shirley MacLaine — and 24 other girls from famous families — worked with a design house (Elie Saab Haute Couture), which dressed her in a beautiful dark blue dress for the evening. She then attended the formal presentation — her official coming out — which was followed by a dinner and then the ball, where she danced with her date, Swiss up-and-comer Brandolino Gritti.

It wasn't all self-serving. There was also a charity component, benefiting Enfants d’Asie, a girls-help-girls humanitarian association, launched in 1991, promoting women’s education in South East Asia.

Isabel spoke to Figaro magazine prior to the big night and said that she surprised herself when she agreed to participate.

"I admit initially I was not very excited by what I thought to be a kinda boring aristocratic gathering," she said. "But it is ultimately very international, modern and fashion[able]."

Having it in Paris was also a selling point for her. "It's magic," she noted.

In the same interview, she talked about her ambitions to become a director, saying her "parents gave me unconditional love for [movies]." She also listed Bening as her idol, calling her "the strong woman" in her life.

Isabel isn't the first celeb offspring to party the night away (in Louboutins!) at the event. Scout and Tallulah Willis, Francesca Eastwood, and Camelot kids Kathleen and Kyra Kennedy also made their debuts at the debutante ball in years past.

Isabel's group this year included Viola Jacobsen Mikkelsen, whose dad, Mads Mikkelsen, appears on Hannibal; computer wiz Michael Dell's daughter, Juliette; and model Pat Cleveland's daughter, Anna Cleveland von Ravenstein.

Isabel is one of four children of Warren and Annette. Her siblings include LGBT advocate Stephen, who is a transgender male, Ben, and younger sister Ella.