Kinnikuman: Justice Superman vs. Ancient Superman

While Kinnikuman is on vacation with Mari-san's kindergarten class at Easter Island, the young wheelchair-bound Kouichi-kun laments being with an idiot like Kinnikuman, preferring to instead be with his favorite Seigi Choujin Buffaloman. Meanwhile, the other Seigi Choujins are also vacationing at ancient landmarks.

Kinnikuman: Counterattack! Hidden Space Superman

As the whole world watches the Choujin Rugby game on TV, the "Underground Space Emperor" Hydra King has his Underground Space Supermen kidnap Robin Mask. Their aim is to lure out the Seigi Choujins and then attack them using the Robin Memo, which contains info on all of the Seigi Choujin's weaknesses. Watching on TV all over the world, Kinnikuman and the Seigi Choujins get together and head for Planet Hydra.