A vast fully-rigged warship, a First Rate of the navy of a fading Empire, plies the seas. In a world where gunpowder does not exist and the use of magic is commonplace, the Renown bristles with catapults and other missile devices.

She is not a happy ship. Under the command of a sadist and his brutal first officer, whispers of mutiny foment. Two junior lieutenants, a convicted and pressed thief-highwayman, a cashiered former infantry sergeant, a warrior woman from the ice wastes of the far north and the mild-mannered ship's Boatswain are at the heart of the plot.

In the dead of night, armed groups form all over the Renown. As the mutiny is sprung, her captain is captured and reveals a surprise of his own. The mutineers find themselves fighting not just the officers and midshipmen of their own vessel, but a new and unexpected enemy.

In a desperate battle, the advantage swings first this way, then that. Old adversaries settle personal scores. Some of the mutineers suspect duplicity in their ranks. Come the dawn, who will command the Renown?