In 1796 war with revolutionary France has turned the Caribbean into a battleground for the last three years. On the island of Grenada a young leader, Julien Fedon, is inspired by the success of the slave revolution in St. Domingue. Taking advantage of the turmoil, his rebel forces strike at their British masters.
With the conflict a bloody stalemate and all except the capital of Grenada under rebel control, the British despair as no troops can be spared to turn the tide. The beleaguered British turn to Commander Evan Ross and Lieutenant James Wilton to infiltrate the rebels, hoping they can learn their plans and find a way to break the impasse.
Lieutenant Wilton successfully infiltrates their foes, but falls in love with the mistress of Fedon, a beautiful mulatto woman serving as a spy for him. With Lieutenant Wilton under suspicion and in increasing danger, Commander Ross is desperate to succeed as the bloody final battle looms.