Late one night, a mysterious spacecraft touched down on the water in a lake encircled by a tranquil forest. The beings who emerged from the vessel abducted Professor Katou, a leading figure in space engineering, along with his family.
The professor's second son, Yuuji, an American football player who had run away from home, was unaware of the kidnapping as he was in the middle of a game.
Watching Yuuji from the sidelines were four young people: Mark, Dickey, Franco, and Yuri. This group of four psychics had been undergoing training in a secret base. They had witnessed the previous night's events and concluded it was an alien invasion. Convinced that their only recourse was the transforming robot Baratack, they used their psychic abilities to abduct Yuuji.
Baratack could only be activated when Yuuji's power combined with that of the other four, acting as one. When the five, including the bewildered Yuuji, shouted "Pentagoras Unite!" together, Baratack appeared. Overcome with fierce anger, Yuuji's fighting spirit ignited to crush the Golteus reptile army.
