Earth is still in danger: aliens from planet Zeraz are willing to invade our planet because theirs is being swallowed by a Black Hole. Led by Great Darius and his four generals, they begin seeding death and destruction. When an ESP warrior is killed by aliens, professor Hi-Tech understands the danger and builds the huge Space Dragon (Daiku Maryuu) piloted by Pete, and the gint robot Gaiking whose pilot is Sanshiro Shiwobuki, an ex-baseball player. Daiku Maryuu is a big dragon shaped spaceship and his head is the Gaiking torso. When the Gaiking enters the action, Daiku Maryuu launches other Gaiking's components and then it re-unite neck with tail, becoming unbreakable. The story chronicled the battle between the crew of the semi-transformable carrier Daikuu Maryuu and the Super Mecha Gaiking against an invading race of aliens from the planet Zela, whose home planet is facing destruction by a black hole. The robot Gaiking was piloted by a baseball star named Sanshiro Tsuwabuki