Osamu Tezuka's Last Mystery of the 20th Century

Original title: 手塚治虫が消えた？！20世紀最後の怪事件

Osamu Tezuka is going to a 21st Century new year's party with all the characters he made. One thing leads to another and he ends up missing! It's up to his most popular characters to find out what happened to him and get him back safely before the rest of the guests show up.