Late summer, 1775, General George Washington discovers that his cache of gunpowder has dwindled to a mere nine shots per man. Desperate, he adopts the plan designed by a group of Rhode Island patriots - send a ship to Bermuda to capture British powder known to be there - as well as their recommendation for the man to lead to the mission: Captain Isaac Biddlecomb. But the plan is a trap, set by a traitor among the patriots, and one from which even Biddlecomb cannot escape. With treachery threatening the revolution, Washington dispatches his aide-de-camp, Major Edward Fitzgerald, to hunt the turncoat down. Meanwhile, Biddlecomb must rely on native cunning and seamanship to free his men and his ship, and to bring to the army near Boston the gunpowder that is the lifeblood of the nascent fight for liberty.