Mr. Osomatsu the Movie

It has been 10 years since the sextuplets graduated from Akatsuka High. One day, they are invited to a reunion party. They attempt to lie about their lives at the reunion but end up humiliating themselves instead. Disgraced, they return home for a night of drinking to forget their humiliation. When they wake up the next day, they discover that they have travelled back in time to 10 years ago. Now they are in search of their younger selves, who might hold the answer to returning to the present.