Director Daisuke Tengan has finished shooting his new movie, titled "Sekai de Ichiban Utsukushii Yoru" ("The Most Beautiful Night in the World").

An original script written by Tengan himself, the movie is themed around Japan's declining birth rate, which is one of the biggest problems currently facing the country. The story starts with a young girl telling a secret about her own town, said to have the highest birth rate in the nation.

Tomorowo Taguchi plays the starring role as a newspaper reporter demoted to the town 14 years ago. Ryo Ishibashi is an ex-radical trying to start a "sexual revolution," and former Takarasienne Sarara Tsukifune plays the gentle "mama" of a snack bar. Other cast members include Shiro Sano, Akira Emoto, Shunsuke Matsuoka, and Yukiya Kitamura.

One of the picture's highlights is a 50-person sex scene, alluded to in the film's title. Naturally, Ishibashi's character is a participant in the event. While the scene may sound similar to the 750-person orgy scene in Tom Tykwer's "Perfume: The Story of a Murderer" (which got a release in Japan last year), Tengan's film is unique in its connection to a real national problem.

"Sekai de Ichiban Utsukushii Yoru" is set to open in theaters this May.