Dr Steven Dunbar of the Sci-Med Inspectorate is sent to investigate an apparent attack by animal rights activists on a research institute in rural Norfolk where they work on vaccine design. The director of the institute has been murdered during the attack after having been horrendously tortured and several experimental monkeys have been released into the wild. While police interest centres on the murder, Sci-Med's interest is centred on what the escaped animals might be infected with.

Steven is assured that it was only influenza virus but becomes suspicious when he finds out that the army has been called in to hunt down and kill the freed animals – wearing biohazard gear. It transpires that .....