Calvary Gaol, standing bleak and forbidding on the Cumbrian hillside, exerts a curious hold over Georgina Gray. For her family's history is closely bound up in its dark and terrible past. It's there that her great-grandfather worked as a prison doctor in the 1930s; where his involvement in a bizarre experiment would change the course of his life forever. TV presenter Chad Ingram is fascinated by Calvary too. For he plans to conduct a new experiment in the now-disused gaol - an experiment that will take place in the brooding desolation of the old execution chamber. Chad's experiment and Georgina's curiosity will have horrifying consequences. For someone has their own reasons for suppressing the shocking truth about Calvary. Someone who will go to any lengths to ensure the past remains buried . . .