In March of 1745, a fleet of ninety ships set sail from Boston under a cloud-ridden sky, with a stormy sea threatening outside the harbor.  They were heading for the jagged coast of Cape Breton Island to stage a surprise assault on the "impregnable" Fortress of Louisburg.  This is the story of that incredible attack, and of Caleb Hatch, a young Boston lad chosen to record the events.

Tracing the incidents that led to the siege, the author tells a story of mystery, intrigue and high-pitched adventure.  The French at the great Fortress of Louisburg had been preying on the New England ships, and as ship after ship fell, laden with rich cargoes intended for Boston, the spirit of revolt had grown.  Fearing the French would strangle trade and starve the city of Boston, the enraged colonists took matters into their own hands, and with neither the advice nor promise of help from England, launched a fierce attack against the enemy.

Caleb's part in the bloody battle, how he uncovers the secret of a mysterious map and uses it to plot a course in the final storming of the walls of Louisburg, makes a tale that explodes with action, tyranny and courage.

From the dust jacket