Kei's resurrection is the moment everything becomes uncertain, even his own morality. The show doesn't give you a villain to hate or a hero to root for, just a chain of people making impossible choices while hunted by a world that sees them as monsters. The 3D animation is visually rough, but it's also what makes the supernatural dread feel genuinely alien and wrong. By the finale, you realize the real terror isn't Ajin abilities, it's how easily a desperate, immortal man becomes exactly what society fears him to be.
Kei Nagai gets hit by a truck and should die on impact. Instead, he wakes up completely healed. That's when his life implodes. He's an Ajin, a nearly unheard-of immortal being, and the moment his existence becomes public knowledge, every government and black-market organization on the planet wants him. Dead or alive doesn't matter. Specimen is the only word they understand. Forced into hiding with nowhere safe to go, Kei has to figure out what he actually is before survival instinct forces him to become the very threat people fear. His newfound immortality comes with abilities he doesn't understand, and every discovery feels more disturbing than the last. The deeper he runs, the clearer it becomes that being unkillable might be the worst curse imaginable. Around him, the world transforms into a hunting ground where trust is a luxury and violence feels inevitable.