November, 1381. London has been rocked by a series of bizarre and brutal murders. The corpses of a number of prostitutes have been discovered, their throats slit, their bodies stripped; in each case, a blood-red wig has been placed on their heads.

At the same time, a mysterious explosion rips through a royal war cog bound for Calais, killing all on board. Could there be a connection?

Summoned to assist in the investigations by Sir John Cranston, Brother Athelstan uncovers rumours that the mysterious Oriflamme is responsible. But who - or what - exactly is he . and why has he suddenly reappeared after almost twenty years?