It is 1740 and Louise Fletcher, a young dairy maid on an Essex farm, has been warned of the lure of the sea for as long as she can remember. But when she is offered work in the bustling naval port of Harwich, as a lady's maid to a wealthy captain's daughter, she leaps at the chance to see more of the world. There she meets Rebecca, her haughty young mistress, who is unlike anyone Louise has encountered before. Intertwined with her story is fifteen-year-old Luke's. He is drinking in a Harwich tavern when it is raided by Her Majesty's Navy. Unable to escape, Luke is beaten and press ganged and sent to sea on board the warship Essex. He must learn fast and choose his friends well if he is to survive the brutal hardships of a sailor's life and its many dangers, both up high in the rigging and in the dark below decks.