You're watching a 1986 space opera that refuses the obvious choice: the son of a disgraced captain hunting for proof his father wasn't a coward, caught between a government that branded him a traitor and a moving planet that might not be an enemy at all. The show believes in co-existence in an era of anime that thrived on total war. By the time you understand what Dr. Sugita actually chose, you're no longer watching a revenge story, you're watching a son inherit his father's impossible faith.
Two years after his father vanishes during a controversial first contact with the approaching planet X23, Susumu is pulled into an underground resistance against Earth's military. Dr. Miya recruits him for White Pegasus, a covert medical rescue unit equipped with experimental shrinking technology that allows operatives to enter human bodies and perform impossible surgical interventions from within. When X23 finally arrives in Earth's orbit, it brings the Hues: alien beings with motives nobody fully understands. As tensions escalate between Earth's military and the mysterious visitors, Susumu discovers his father's philosophy of coexistence may hold the key to survival. But the Hues have their own agenda, and they're targeting the people closest to him. Caught between governments that want war and aliens pursuing a hidden purpose, Susumu must master his team's cutting-edge technology while questioning everything he's been told about first contact. The line between rescue mission and survival becomes increasingly blurred as the real reason X23 came to Earth begins to surface.