Isadora Peabody is the brilliant but socially inept sibling in an otherwise perfect family. And although she struggles to fit into Boston society, her awkwardness dooms her to repeated failure. Fate intervenes when she learns that a sea captain, Ryan Calhoun, is in need of an interpreter for his next voyage to Rio. And despite Ryan's adamant opposition to hiring a female interpreter, Isadora gains a berth on his ship, thanks to a little blackmail.

Life aboard ship and away from the strict confines of Boston society finds Isadora losing weight, gaining confidence, and blooming like a rose. She befriends the motley crew of rough sailors, and in turn, they become a charm school of sorts, tutoring her in gracefulness--which comes in handy when climbing the rope rigging--dancing, and friendship. Isadora's transformation fascinates Ryan, but he is determined to stay away from her for he has secretive, dangerous plans. Unaware of Ryan's interest, Isadora struggles with her growing attraction to the reckless sea captain. But before they can resolve their feelings, prior commitments surface and endanger their chance of finding a happy future together.