All the Seas of the World by Guy Gavriel Kay

Returning triumphantly to the brilliantly evoked near-Renaissance world of A Brightness Long Ago and Children of Earth and Sky, international bestselling author Guy Gavriel Kay deploys his signature 'quarter turn to the fantastic' to tell a story of vengeance, power, and love.  

On a dark night along a lonely stretch of coast a small ship sends two people ashore. Their purpose is assassination. They have been hired by two of the most dangerous men alive to alter the balance of power in the world. If they succeed, the consequences will affect the destinies of empires, and lives both great and small.  

One of those arriving at that beach is a woman abducted by corsairs as a child and sold into years of servitude. Having escaped, she is trying to chart her own course—and is bent upon revenge. Another is a seafaring merchant who still remembers being exiled as a child with his...