While attempting to halt a mugging by two thugs, the Grim Ghost is attacked by the demon Brimstone. His goal - to topple Satan and rule in Hell. Brimstone gives the Ghost a choice, side with him or perish.

When he recovers, the Grim Ghost seeks out Satan for answers. He finds not only Hell, but Armageddon, a battlefield littered with corpses.

Satan, unable to battle Brimstone on earth, appoints the Grim Ghost to do battle with him. He endows him with additional powers and provides him with assistance in the form of Lady Sarah Braddock, the woman who betrayed him and turned him over to the authorities to hang. Much to his dismay, he is forced to accept her help.

The unlikely duo soon encounter Brimstone. The demon is too powerful however, and he soon overpowers both the Ghost and Lady Braddock. In a last ditch attempt to defeat Brimstone, he pierces the demon's mind. Brimstone cries out in anguish as he realizes that he will cease to exist the moment that he strikes down Satan, a precaution that Satan also took with the Grim Ghost.

Knowing that he can never rule in Hell, Brimstone simply ceases to exist.