In the midst of the Spanish Civil War, Luis Denard (Charles Boyer), a former concert pianist and composer, travels to England as a confidential agent of the Republican faction (Spanish Civil War) government. His mission is to buy coal or to deny it to the Fascist rebels. On the ship, he meets bored rich girl Rose Cullen (Lauren Bacall), whose father, Lord Benditch (Holmes Herbert), heads the firm with which Denard will negotiate.