When the little slave girl was born, plantation owner John Penrose bestowed the name Cassiopeia for the small birthmark placed low on her neck identical to that of the chair in the constellation Cassiopeia, named for an Ethiopian queen.
Growing up as a house slave on Roselawn Plantation, Cassie Omoru dreams of being free and helping her people. But when her well-being is threatened by Enoch Penrose, the depraved son of the plantation owner, she is whisked away to St. Benedict's Monastery on Skidaway Island, Georgia. Enoch swears he won't give up until Cassie is his.
Meanwhile, under the loving guidance of Sister Bernadette, Cassie blossoms into an intelligent and accomplished young woman. When the French army arrives to aid the Americans in their attempt to free Savannah from the British, they recruit her as an interpreter, and she falls in love with a French-Haitian soldier, Andre Dupre.
But even as the battle subsides, danger looms for Cassie as Enoch pursues her and Andre through the sea islands of Georgia as they seek sanctuary in Spanish Florida. She prays that her namesake in the sky can protect her from evil.