A kid and four cyborg dogs are literally humanity's last defense against an alien invasion nobody believes is coming. The absurdity hits different when you realize the professor had to weaponize his son's pets because actual governments wouldn't listen. This is 1972 mecha stripped down to its purest revenge fantasy: four loyal animals given the power to save the world, led by a boy who's already lost everything to the people who should have protected him.

Professor Hayashi watches his warnings about an impending alien invasion fall on deaf ears. While the world dismisses his claims, rescue comes from an unexpected source: four dogs his son Tsutomu has befriended. The professor then turns the animals into cyborgs with remarkable powers. With young Tsutomu leading them, the canine quartet of Queen, Ace, Jack and Joker take up the fight against insect-like invaders from the Planet Devil. The four can merge and transform into a spaceship called Liner. This roughly 50-minute sci-fi mecha action film was screened in 1972 as one of the programs of the Toei Manga Festival. The story is original, built on the concept of Hiroshi Sasagawa's manga Maken Goro.