In the kingdom of Avelorne, Marian Vail, a gifted young musician from Briar Glen, enters a contract marriage with Duke Adrian Ravenscroft, who heads the Royal Mercantile Guild, to raise twenty thousand gold coins for her father's cure. She returns to the guild as a cleaning maid, still bearing the stigma of being framed by Isolde Vane for stealing sheet music. Surviving one scheme after another—a planted earring, a faked fall injury, and a hired kidnapping—Marian wins back the White Stone River trade route through a musical duel, becomes the guild's youngest Chief Musician, clears her name at the annual celebration, brings Isolde to justice, and finds true love with Adrian.
