Mycroft Holmes, charged with ensuring the personal safety of Queen Victoria, calls on his brother for help when a number of attempts have been made on her life and when two unexplained deaths occur amongst the staff at her Scottish residencies.
Accompanied by Dr Watson, Sherlock Holmes goes north by train, examining the few facts Mycroft has been able to cryptically supply.
To Watson's bafflement he is sure there is a link between these deaths and the murder in the old royal apartments at Holyrood of the secretary to Mary, Queen of Scots: a killing which left a bloodstain that daily refreshes itself and in a room where voices can be heard in the darkest hours of the night.
Can Holmes's extraordinary deductive powers solve the historical crime as well as the contemporary one?
An original, beautifully crafted mystery story which is also a respectful homage to the master of the whodunnit.