Ye Yan, callsign "Thunder Dragon", leads the Shadow Team defending the northern border. Gifted with lightning powers and tech genius, he hides a strategic mind behind a careless facade. After his family was massacred by the "Black Bear" organization when he was ten, he and the girl Yaoyao alone survived. He initiated the "Burning Heart" project for long-range combat, but his brother-in-arms Zhou Chen corrupted it by implanting the tech into humans. As Zhou flees, Ye Yan hunts him down, torn between justice and past loyalty.