Monitor is an observation satellite/ study centre, manned - if that is the right word - by a collection of beings from different parts of the Galaxy. The object of their attention is a small blue planet in orbit around an isolated medium-sized star on the edge of one of the galaxy's spiral arms. It is, of course Earth, but they call it 'The Object of Our Attention', or 'The Object' for short. The reason they are observing the Object is because it is the lair of an evil entity that - hounded by the Lord of the Guardians and a host of his followers - took refuge there at the end of the last great galactic war. The victorious Lord has set in motion a complex plan to entice the Entity out of its refuge in the molten core of the planet, so that it can finally be destroyed. He has not divulged the plan to any of the observers however, and the Guardians are an uncontactable enigma.