When the Court clockmaker, Mr Urseau, is found dead in his workshop - a dagger in his chest and a key clutched in his hand - rumours start flying. Was the murderer his young assistant? Or maybe his wife? Both could be after Urseau's private treasure. And where is the key from? What is it for?

Lady Grace, Queen Elizabeth's own Lady Pursuiviant, is determined to get to the bottom of all these questions. But things get even more complicated when Grace discovers that a mysterious clock was delivered to the palace on the day Urseau was killed . . .