Dorothy Arden is private secretary to Godfrey Lovell, known as the Croesus of Wall Street. His western partner is Daniel Casselis, who has a daughter, named Dorothy. Lovell has a son, Robert, and the two financiers are trying to arrange a match between their children. But Robert falls in love with his father's secretary, and marries her, but on returning home to tell dad, he finds Lovell is ill and has gone on a long sea voyage to recuperate. Bob is sent to Chicago to see Casselis and invite him and his daughter to come on the cruise with Lovell, and Dorothy is greatly distressed at this turn of events. Bob reassures her, however, and still they do not tell his father. Bob meets Miss Casselis on the Limited as she is returning from an Eastern trip and they become friends. Meanwhile, Dorothy has determined to go on the yachting trip, so when the whole party arrive at Frisco Bob finds his wife awaiting them. Many amusing complications occur during the voyage and jealousies are aroused. The yacht anchors off a lonely island in the Pacific and Bob, with the two Dorothys, goes ashore. The yacht is driven out to sea by a terrible storm, leaving the three stranded on the Island of Surprise. Bob is hurt in a terrific landslide and the blow causes him to lose his memory. Dorothy tries in vain to call to mind his marriage to her, and Miss Casselis, thinking Dorothy is merely bluffing, is not to be outdone and claims Bob is her husband. Bob finally settles an uncomfortable situation by telling the women he will simply remain their friend and protector. Meanwhile, the yacht has had to send out a boat for the nearest land, owing to engine trouble, and a man-of-war is met. She is directed to the island, and arrives just in time to drop a shrapnel among a horde of island savages who are attacking the three castaways and just about to annihilate them. Rescued by the navy men, the three castaways are reunited with their party. Bob recovers consciousness and recognizing his wife, all ends in forgiveness and happiness.