Tower of London: 1214

Maude de Mandeville is dying. Murdered by a poisoned egg for rejecting King John’s advances. As she stands before Death, she makes a pact with the Devil to avenge her murder and return as a ghost to protect her only son with the help of her inherited witch’s powers.

Sixteen years later her son, William de Mandeville, declared a traitor by John's son King Henry III, arrives at the Tower in disguise but he is determined to regain his status as the Earl of Essex at any cost. However, he quickly becomes torn between two very different women – Emma, the alewife’s daughter, and Princess Isabella, daughter of his mother’s murderer and sister to the current King. Their lives will be changed for ever.

Over the course of some forty years, Maude’s ghost plays a deadly game with the Devil, as she tries to protect her son and his family and gain vengeance for a death she did not deserve.