Three years ago the very fate of humanity hung in the balance. From out of nowhere, mysterious alien invaders landed on Earth and began to systematically enslave it’s people - turning them into vicious zombies. And they would have succeeded if it wasn’t for one man. Halloween Harry. Working with Diane, his trusted Mission Controller, Harry single-handedly kicked the alien invaders’ butts back to their home world - never to be seen again. Until now. It's the day before Halloween, and with a grudge to bear, they're back. Nastier and meaner than ever. The aliens known as the Non Human Alliance (NHA) want nothing more than to destroy all of humanity. This time they’ve kidnapped one of Earth’s greatest scientific minds and forced him to create a more powerful Zombie transformation machine. It’s up to Harry and Diane to save the world once again. Armed with an impressive array of weapons, including Alien Seeking Missiles, Micro-Nukes, Thermal Grenades and the ever trusty Photon Cannon, Harry and Diane are ready to dispense some instant Earth justice. Racing through zombie infested parks, slime soaked sewers, booby trapped beaches, monster ridden office blocks, robot controlled factories and alien plagued ships, you are the last best hope to save humanity.