You are the title character Maru. One day you are walking with your girlfriend Cori in Central Park and she gets kidnapped by Muramasa, a being capable of appearing and reappearing in the blink of an eye. Convinced that the authorities would think you were nuts if you told them what happened, you decide to rescue Cori on your own. As you walk, jump, swim, and battle your way through the fifteen levels of play, you will face a number of enemies including classic monsters such as Frankenstein, Medusa, Dracula, and the Wolfman. You are equipped with a constant supply of throwing stars and can upgrade your arsenal to include weapons such as boomerang bombs, magic missiles, and sonic waves. If you find a magic scroll, you can split into several Marus, each of them having the ability to attack. Most of the action takes place on dry land, but three of the levels are underwater where you'll be armed with an unlimited supply of spears.