在美国秘密基地，美军正培养新菌。不料在试验过程中出错，成为可怕的病毒。受感染的特工突然发狂变成丧尸。混乱中华裔特工Harry被丧尸弄伤，把病毒带回香港。警察Marco（冯德伦）、古惑仔碎料（李灿森）与特工May力抗丧尸，到后来才发现香港已陷入紧急状态，整个地区被丧尸控制……

CIA Agent Harry is bitten by a man who was part of a deadly experiment involving the ability to withstand pain. The bacterium has a virus, causing the victim to become a zombie. Upon Harry's arrival in Hong Kong, after rejection from his ex-girlfriend, the virus begins to take effect. He kills a call girl and is arrested after a gang fight. When he is in prison, Harry transforms into a Zombie King and transforms nearly an entire Triad gang into his personal horde. Soon, the police department becomes a House of the Dead. It's up to a police officer named Marco, Harry's ex, and a Triad member named Cheap to stop them before it's too late.