You'll start out with $10,000 in your bank account. You'll have to use part of this money to purchase all the things you'll need.

Then, you'll be given a map of the city. Whenever ghosts enter one of the buildings, the building will blink. And you'll have to make tracks to get there as fast as you can.

Once you reach the building, you'll use your Ion Beams to trap the ghosts. When you get all of them, the scene returns to the map and you start looking for ghosts all over again.

Sometimes you'll have to return to headquarters. To pick up a new man. To recharge your Ion Beam. Or to empty your ghost traps.

When the Marshmallow Man enters the scene, you'll have to drop everything and confront this monstrous mess. Sneak your men past him to enter the temple of Zule.

Once you've entered Zule, you'll have to climb the stairs -- attacking Roamers as you go -- and try to make it to the top.

There, at the top of Zule, you'll have one last assignment. Destroy Gorza.