In 2125, a century after the green-comet “Emerald Fall,” the alien substance Muk still taints Earth. Two powers remain: Ant City and PAC, a militarised regime ruling from the sea fortress, the Crown. Ant City’s flagship, the ARK — a retrofitted WWII battleship — carries a giant repair mecha meant to restore the city’s shield. PAC plans to hijack the ship, impersonate its crew, and deliver the mecha embedded with malware to disable the shield from within. 18-year-old Mulan, raised aboard the ARK by her father, Captain Hua Muzhi, is unknowingly the only human fully bonded with Muk. Anticipating sabotage, Hua hides in a panic room and locks the engines. As long as he remains hidden, PAC cannot proceed. When the assault begins, AI drone MUV-I is activated and executes Hua’s secret Shan Hai Guan protocol, guiding Mulan through hidden corridors. But her search for Hua accidentally helps PAC mole Aiden trace his location. Aiden detonates charges, separating them, and PAC regains control. Hua reaches the bridge to destroy the mecha but is killed. Mulan awakens Muk’s power, defeats Khan, and fires the main gun — vaporising the Trojan mecha. Muk glows again as PAC retrieves her body. She lives.