In the deep of space, a starship is hijacked. The vice president of a powerful corporation is onboard, alongside a deadly monster, Zeiram. Young bounty hunter Iria is tasked with executing a rescue mission before the authorities catch on.

Narrowly avoiding death, Iria must find her way back home on a strange planet. When Zeiram is discovered to have escaped the blast, Iria must team with sidekick Kei to stop a reign of evil.

Iria returns home to find her apartment ransacked and that the entire record of the starship escape has been wiped clean.

Now a fully-licensed bounty hunter, Iria goes on a mission to save Dr. Touka, the man who knows more than any about Zeiram.

As Zeiram's clones multiply and terrorize, Dr. Touka tries to get the truth out about the monster.

Iria faces Zeiram for a final showdown. In order to put an end to the monster's reign of terror, Iria must team with Dr. Touka, Kei, and Bob.