December 1773. Midshipman Bolitho's ship, the Gorgon, is laid up in Falmouth for refitting, and the young sailor - now seventeen - looks forward to a peaceful Christmas with his family.
But Cornwall is now a violent place. Smuggling is rife, witchcraft abounds, and ugly rumours lead to the murder of a revenue officer. As the Gorgon lies helplessly in dry dock, piracy and wrecking becomes a dangerous threat to the undefended shores.
Then one day the Avenger, a small man-of-war, sails into Falmouth, captained by Richard Bolitho's brother; and before long the young midshipman is embroiled in a fierce and bloody struggle for the domination of the seas.