The Pearliad

In 'The Pearliad', each person has an arca, which is set on the Earth at the same time as they are and leaves when they depart. Most people don't see their own arca in their lifetime - they just know that it's out there somewhere, their biggest vulnerability, the key that unlocks the door to death. It could be anything, from a ribbon to a button on a coat. And the ruthless citizens of the Roman Empire know that nothing reaps more power than holding another man's life in their hands.