[1] The novel's protagonist, the “crap artist” of the title, is Jack Isidore, a socially awkward, obsessive compulsive tire regroover who has been consumed with amateur scientific inquiry since his teens.

He catalogs old science magazines, collects worthless objects, and believes disproved theories, such as the notions that the Earth is hollow or that sunlight has weight.

Broke, Jack eventually moves in with his sister's family in a luxurious farm house in rural West Marin County, California.

He also joins a small apocalyptic religious group, which shares his belief in extra-sensory perception, telepathy and UFOs and believes the world will end on April 23, 1959.

Jack's sister, Fay Hume, is a difficult and subtly controlling woman who makes life miserable for everyone close to her, especially her misogynist husband Charley.