Undersea Super Train: Marine Express (海底超特急 マリン・エクスプレス, Kaitei Chōtokkyū Marin Ekusupuresu) is an anime television film created for the Nippon Television Network's annual 24-hour charity program, Ai wa Chikyū o Suku, which roughly translates to "Love Saves the Earth". The movie contained a veritable "Who's Who" of Tezuka's notable characters. Each one had an important role, and many of them had individual, intertwining stories which would overlap with the ones of others. To coincide with the central theme of the charity program, the movie emphasized on the dangers of environmental destruction, and that such disasters can be overcome by banding together.

For the previous charity special in 1978, Osamu Tezuka and Tezuka Productions created One Million-Year Trip: Bander Book. The year after, when the special was held again in 1980, Tezuka and Tezuka Productions created another film, Fumoon, based on Tezuka's manga Nextworld.