In the Soho studio of Bodies magazine (porn so soft it's "practically marshmallow'') are found four corpses: a photographer, his assistant, an actress-student and a young bodybuilder. Perry Trethowan of London's C.I.D. can't discern a motive for the murders but a few hints point toward the bodybuilder's background. The suave Trethowan finds himself involved in the seedy, naively narcissistic world of competitive body-building. Using a black gym-manager as an undercover decoy, Trethowan penetrates a more sinister, hardcore porno operation that specializes in teenagers