She may be most fondly remembered as Summer Roberts from Fox’s The O.C. (or as Ted’s crush, Cindy for you How I Met Your Mother fans), but tonight at the Tribeca Film Festival, the starlet will be debuting her latest project: a three-part short film series to tout the U.S. launch of ice cream brand Magnum. Other big names like Bryan Singer and Benicio del Toro have collaborated on previous shorts for the brand, and this year the company called on Chanel creative director Karl Lagerfeld to direct Bilson in three different roles — as a model, prima ballerina, and art student. (After tonight’s premiere, only the first film will be available for viewing on Magnum’s Facebook page, but check back in a couple of weeks for EW’s exclusive look at “Art Class,” the third short.)

We chatted with the 29-year-old actress, who also recently finished shooting the pilot for The CW’s Hart of Dixie, about the shorts, working with the king of fashion, and just how much ice cream she ate during the shoot.

ENTERTAINMENT WEEKLY: This is a pretty plum gig. Paris. Karl Lagerfeld. Ice cream. How did you snag the role?

RACHEL BILSON: We were approached by Magnum ice cream, and I knew Karl was initially involved to do the three vignettes. I was so excited because I love ice cream and I love Karl Lagerfeld. That was definitely not a hard choice to make.

Of the three shorts, do you have a favorite?

I played an art student, a ballerina, and a model. Definitely the ballerina. It was fun to pretend like I was a professional, although I had to put on the pointe shoes on for two seconds. It kills! It’s unbearable. You really respect what they go through. You have to commend anyone who puts those pointe shoes on.

Had you known Karl Lagerfeld?

To say I knew Karl…Well, now I can say he knows my name! I had met him on occasions when there were groups of people, but he would never remember [me]. But to be able to actually spend time with him was really great. He’s so nice and funny with a great personality. And he’s a really good director. He obviously has a clear vision, which is a no-brainer since he’s the best designer ever. I thought he was excellent.

Do you have a particular memory of working with him?

He told me old Hollywood directors would walk through and do scenes with actresses and show what they expect with movements and what they want from the scene. I had a lot of fun doing [the shorts], but I haven’t actually seen them. It’s weird to watch yourself, and I’m also nervous because it’s with Karl, and oh my god! What if I didn’t do a good job?

So after three days of shooting with ice cream, how many bowls did you actually eat?

Realistically, over the three days, I’d say in the 25 range. A lot!

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