Two cops are investigating a drug ring that may be led by an American man who saved them when they were kids. But when he kidnaps one's wife, they must fight through an army of ninjas to save her.

Sewage workers Jack and Charlie get involved in an international Asian gang war when Jack helps the boss of a Shanghai gang against one of his rebellious underlings. This underling then strikes a deal with the Japanese Yakuza in the hopes of toppling his boss and become the leader of Shanghai himself. When the Yakuza assassinate the Shanghai boss, Jack pledges to avenge his new friend's death. As he seeks out those ultimately responsible, he does battle with a variety of ninjas and mercenaries from around the world.