A teenage boy follows a drunken moose down a two-dimensional river that cuts through time and matter. Arriving at new worlds outside the realm of reality, he is shocked to witness lands where the laws of physics are optional, logic and common sense mean nothing, and a good sense of humor is needed just to survive. He encounters worlds with varying numbers of dimensions; worlds that make him doubt his own sanity and physical form; surreal worlds and ones that seem an exercise in futility. The inhabitants are as strange as the worlds they occupy: beings who would kill him for questioning their practice of Absurdism as a religion; who create their own reality as they go along; and some whose very existence defies reason. To be able to go back to the world of common-sense - home - he must find an elusive being who has power over all the worlds on the river, but who seems to make the least sense of all. But the being is less interested in helping the boy return home than in introducing him to the universe's greatest mystery.