In the year 203X, Earth faces an extraterrestrial attack. Park Hyunsung, a courageous militia commander, sacrifices himself to destroy the enemy base but finds himself caught in a malfunctioning teleportation device. Suddenly, he wakes up in the body of Ian Alberon, a 15-year-old lord in a world of monsters and magic. As he struggles to adjust to his new environment, he realizes that his enemies may be closer than he thought. The Otherworlders, who possess far more advanced technology, have waged a decade-long war against humanity, forcing Hyunsung to become a fierce warrior in order to avenge his lost family. Trapped in his new body, he sets out to fight with armor and swords against the medieval-like world's monsters, despite the fact that his own enemies may be lying in wait.
