When Arthur’s sword Excalibur is stolen the Temporal Detective Agency is called in to protect not only Arthur and Merlin, but to stop a very clever and cruel person from destroying Camelot itself. To make things worse, this time the TDA has no idea who they’re fighting.

Marlene’s plan takes Tertia and Unita to Rome, Egypt and even to a meeting with Shakespeare, before confronting their enemy in the Coliseum.
But first, if the Agency is to succeed, Arthur must die.... and Merlin and her King have to agree. If they don’t, Camelot will be doomed and History itself could be changed.

That’s the trouble with swords!