Spring, 1549. Sudeley Castle holds secrets worth killing for. England's most dangerous traitor is dead - but his villainy remains alive. John Dee is hunting a secret weapon that could change everything. His orders are clear: find it, secure it, tell no one. Catherine Brandon is fighting to secure an orphaned child's inheritance. She'll do anything for it. Even deceive the man she loves. A Spanish agent schemes from the shadows. An alchemist hides behind a dead man's face. When Catherine accepts help, the price seems small - but her choice will set everything aflame. In the shadowy halls of Sudeley Castle, trust will shatter and love will burn. Some betrayals cannot be forgiven.