“The First Monday in May” opens April 15 at the Bunkamura Le Cinema Theater in Tokyo’s trendy Shibuya Ward (the Japanese title is “Metto Gara, Doresu o Matotta Bijutsukan”). It’s a documentary about a Metropolitan Museum of Art exhibition titled “China: Through the Looking Glass” in 2015.

It was the most attended fashion history exhibition the Met had even seen with more than 800,000 visitors (breaking the 660,000 attendance record for Alexander McQueen’s 2011 “Savage Beauty”). The reason? Apart from the gasp-inducing gorgeous frocks that represent China’s cultural history, the celebrity wattage was blinding: Sarah Jessica Parker, Rihanna, Madonna, George Clooney and other A-listers paraded up the Met’s red-carpeted staircase on the titular benefit night. And engineering the whole shebang was the “devil in Prada” herself, Vogue editor Anna Wintour.

Directed by Andrew Rossi, the film highlights the polite but intense struggle behind the scenes as Wintour and the Met’s costume institute curator Andrew Bolton play a gentle tug of war to find just the right dramatic tones along with carving out a budget, and then orchestrating the whole thing for a Monday night in May. The question of whether fashion can be included in the ranks of traditional high art is at the core of their discussions.

For viewers in Japan, the documentary presents a chance to indulge in two of the nation’s favorite things: fashion and museums. Japan has 384 museums, preceded only by Germany (606) and the United States (2,098). As for the nation’s love of fashion, you have only to go for a walk in Tokyo to witness it first hand.

Having said that, the “Is fashion art?” conversation doesn’t seem to be one that Japan’s museums seem to be interested in. Museums here are notoriously conservative when it comes to choosing exhibitions and fashion designers get few opportunities to show their work in them.

There have been exceptions, of course. An Issey Miyake exhibition opened at the National Art Center, Tokyo, last year around the same time as the annual Met exhibition in New York. And in the early 2000s, the Hara Art Museum in Shinagawa displayed the works of Yohji Yamamoto. Both were successful but nowhere near what the Met was able to achieve.

In “The First Monday in May” art and fashion carefully circle around each other like an amicably divorced couple suddenly finding themselves at the same party. To all eyes, they’re civil with each other but underneath the calm, there brews a storm involving power and money, and Rossi’s film carefully dissects it all. If you’re going to New York soon, you may want to check in at the Met: this year, the costume institute will show Rei Kawakubo and her brand, Comme des Garcons, celebrating “Art of the In-Between.” Too bad Shion Sono isn’t the art director.