All Archer Cobb wants to do is join the navy and help Britain fight the Nazis as World War II begins to rage--like his older brother, William, who is a member of the British Expeditionary Force. There's just one problem: Archer is only twelve years old.

When Archer sneaks off and lies his way into the navy, he soon earns the friendship and loyalty of his crewmates. But after the officers find out how young Archer is, he is sent home, where he must deal with the stepfather he resents and a terrible family secret--until word comes through that the British soldiers fighting in northern France are in trouble, William among them. Desperate to join the rescue effort, Archer steals his stepfather's boat and sets off on his own for the beaches of Dunkirk.

Afraid, yet determined to find his brother, Archer must face the enemy's U-boats in rough waters and bombers in the air, as he navigates to the shores of Dunkirk to take part in a massive rescue operation. But will he manage to find William? And will he and his stepfather find a way to make peace?

From beloved #1 New York Times bestselling author Jennifer A. Nielsen comes a thrilling adventure story about courage in the face of terrifying danger and the lengths we go to for the people we love.