New York and L.A.'s style sets hit Tokyo on Saturday night to celebrate the new Opening Ceremony store in the fashion mecca of Shibuya. And despite their none-too-shabby shopping credentials, they were duly impressed. "I think this is probably the most incredible store I have ever been to," cooed Kirsten Dunst, as co-owner Humberto Leon gave her a personal tour.

The Tokyo flagship—the third in Leon and his partner Carol Lim's OC family—is a dizzying eight-floor fashion wonderland based on OC's shop-in-shop concept, with themed floors heightening the sensory overload. "City of the Future" features Nom de Guerre, Proenza Schouler, and Alexander Wang, who was guiltily taking in the spectacle: "Fashion week is in a week and I am partying in Tokyo?" Other floors include "Office Space," featuring Erin Wasson x RVCA, and "Welcome Home," which houses the Japan-only Opening Celebration collection. The Row designers Mary-Kate and Ashley Olsen wandered around in kawaii rabbit and mouse ears after adding autographs to a few of their pieces.

Later, it was on to Ebisu's LiquidRoom, where the Strokes' Julian Casablancas played a live set of tunes from his new solo album Phrazes for the Young. By evening's end, the locals were suffering from celebrity overdose: Jason Schwartzman, Sean Lennon, and mom Yoko Ono partied along with local notables like actress Rinko Kikuchi, K-1 fighter Norifumi "Kid" Yamamoto, model Yu Yamada, and hairstylist Yuya Nara. "The energy in Tokyo is just insane," said Leon. "It's magnificent." On Saturday night, he was right.

— Tiffany Godoy