Ultraseven. Even after half a century has passed since its initial broadcasting, his story is still etched into people's memories. The story that connects the present as the future of 55 years ago, will be depicted as an 'IF story' that "may have existed" as an episode of the series at the time of its broadcast in 1967, and tell the story of "how it happened."

Based on a manga titled Vampire Princess Miyu. A young girl by the name Miyuu wakes up in Tokyo 1991 but no memory of who she is nor her mother's whereabouts, until she see a vision of her president Zovrinka. He explains to her that she is not from this world, she was born in 2500 during the Great War in the universe, with a special power that can save the earth. He's sending her back in time to fight other people with same power as her and to prevent the planets to collapse. Then she meet sergeant July who works for the other president, she claim that Miyuu is working for the wrong side, but who can she trust.

When GUTS-Select investigate mysterious disappearances, they learn it is work of an evil alien who intends to invade the Earth, called Professor Gibellus. However, just in time, a mysterious woman appears to help GUTS-Select.