The anime film will open in Japan on March 15.
The film centers on the sextuplets at a high school class reunion. There, they see all their former classmates who have become "proper" adults with company jobs. The sextuplets sulk about this and go home and drink until they fall asleep. But when they wake up, a certain scene awaits them.
The film's returning staff members include director Yōichi Fujita, scriptwriter Shū Matsubara, character designer Naoyuki Asano, and Studio Pierrot on animation production. Shochiku is distributing the movie. The film will also include returning cast members.
The Mr. Osomatsu television anime is inspired by Fujio Akatsuka's original Osomatsu-kun manga and "high tension comedy" TV anime, which centered on the Matsuno household with six naughty and mischievous sons (who are sextuplets). All of the sextuplets, including the eldest Osomatsu, are all in love with the same girl, Totoko. The original Osomatsu-kun series followed the family when the sons were 10 years old. Mr. Osomatsu re-imagines the original manga and TV anime with the sextuplets as adults.
The Osomatsu-san Ouma de Kobanashi special aired in Japan in December 2016, and Crunchyroll streamed the anime under the title "Mr. Osomatsu JRA Special 2016." The 24-minute special is part of the "Hashire! Oumatsu-san" collaboration between Mr. Osomatsu and the Japan Racing Association. The collaboration also includes a series of six new anime shorts titled "Mutsugo to Ouma no Monogatari" (The Story of the Sextuplets and a Horse).