Liverpool 1861, on the eve of the American Civil War. Henry Noyse, bosun's mate on the transatlantic liner 'Arabia', and his girlfriend Jane become embroiled in diplomatic intrigue following a chance meeting with US Navy captain and confederate sympathizer Matt Lagarde. Lagarde, who had travelled to Liverpool to raise funds for an independent privateering venture is pursued by an overzealous US marshal. The action, which involves romance, treachery and murder, takes place in Liverpool, New York, and Halifax, Nova Scotia.