When Mrs. Galloway, who suffers from heart disease, finally passes away it comes as no shock to the staff at Berebury Hospital. Abel Granger's family had also been long prepared for his death that same morning.
So why then has Mrs. Galloway's son called in Detective Inspector Sloan to investigate, and why is Abel Granger's doctor so uncomfortable?
The only thing that seems to link the two patients is the Cardigan Protocol, a drug trial being carried out for Gilroy's, a pharmaceutical company.
This, along with the unexplained disappearance of the doctor in charge of the drug trials and the surprising break-in of the Gilroy's headquarters by a group of animal rights activists, leads D. I. Sloan to suspect that something much more sinister than coincidence is afoot.