Charles II has been restored to the English throne for one year. He presides over a court swirling with intrigue, where friends and enemies mingle and conspire. Our hero, 22-year-old Matthew Quinton, is from a family loyal to their monarch. Pressed for time and facing evidence of yet another plot against his person, the king gives Quinton command of a ship and tasks him with a delicate mission: to sail to the western isles of Scotland, intercept a cargo of weapons destined for the king's sworn enemies and blow the conspiracy apart. Matthew is not an experienced seaman his last ship was lost with all hands. Dreading another failure, he is determined to master the sea and overcome his own fear and ignorance. But he has other difficulties to face on the voyage north: a resentful crew, a suspicion of murder, and the growing conviction that betrayal and treason lie closer to home than he thought.