A 1979 Japanese tokusatsu kaiju film produced by Tsuburaya Productions, consisting of re-edited material from the original television series Ultraman. Ultraman: The Great Decisive Battle was the 1st movie of the third Showa phase (Jissouji's Ultraman being first and Ultra Brothers vs. The Monster Army being second) and because of this Tsuburaya decided to make this a reunion of the last 12 Ultras (aside from Ultraman 80 which hadn't come out yet). Tsuburaya decided to give this a different tone than Jissouji's Ultraman, having more new scenes and appealing to the all-Ultra fan.

Home drama about tin craftsmen and their families in downtown Tokyo. Though poor, they do not lose their cheerfulness or give in to oppression.

In this recorded stage debut of the original Ultraman, self-proclaimed world's number one kaiju tamer, Eiji Tsuburaya introduces Ultraman, the Science Special Search Party (SSSP), and various kaiju.

Keizo Tsujiguchi believes his wife Natsue was having an extramarital affair when their child was kidnapped and killed. He believes of her extramarital affair she was unable to watch over their child properly and blames her for their daughter's death. To exact revenge on his wife, he then adopts the killer's child without telling the truth to his wife or their newly adopted child.

The film consists of re-edited material from the original television series Ultraman. Episodes 1, 8, 26, and 27 were used for the film. They were narrated by Hikari Urano as an "Ultraman Documentary". Allegedly only one new scene was shot, and that some parts of the movie where shot in black and white for unknown reasons. The movie screened at the same time as the Toho movie King Kong Escapes.