Kinnikuman: Gyakushuu! Uchuu Kakure Choujin  

Kinnikuman: Counterattack! Hidden Space Superman, キン肉マン 逆襲! 宇宙かくれ超人, キン肉マン 逆襲！宇宙かくれ超人

The "Underground Space Emperor" Hydra King is kidnapping Robin Mask during the worldwide broadcast of the Choujin Rugby game. Their goal is to use the Robin Memo, which contains information on the Seigi Choujins' weaknesses, to lure out and attack them. Meanwhile, Kinnikuman and the Seigi Choujins are watching the event unfold on TV from all over the world and decide to head for Planet Hydra to rescue Robin Mask.

Counterattack! The Underground Space Choujin is the fourth theatrical film based on the anime series Kinnikuman. It was released in Japan on July 13, 1985 alongside Dr. Slump and Arale-chan: Hoyoyo! Dream Capital Mecha Police, Captain Tsubasa: Great Europe Play-Off, and Dengeki Sentai Changeman: Shuttle Base Showdown. It is set after the Golden Mask Arc.It is the first film to feature the character Geronimo and the last film where Eiji Kanie supplies the voice of Ramenman. It is also the shortest film of the series. It is based on theKinnikuman special chapter Robin Memo (ロビン･メモ).(Source: Kinnikuman Wiki)