A Hennessey and Yellich Mystery When four postcards are sent anonymously to the staff of an advice centre, each with the word 'murder' scribbled in a foreign language and the same precise OS map reference, the police are called. DCI Hennessey of the Vale of York police and his team of detectives visit the sinister location and make a chilling discovery: the body of a professional man who had been reported missing ten years earlier...