Newlyweds Henry and Evelyn Langdon are the newest members of the suburban community of Elmhurst, where it is considered fashionable for married couples to engage in harmless affairs. Attempting to conform, Evelyn accepts the attentions of bachelor Bruce Grey, while Henry flirts with Mrs. Hammond. Complications arise when Grey ardently pursues Evelyn, proposing that she accompany him on a trip. She ignores his offer until Henry fails to return home from a date with Betty Turner. Evelyn, unaware that the two are marooned on an island, assumes the worst and runs off to board Grey's train. Returning home the next morning, Henry finds a note from his wife and races to the train, catching it just as it is departing. Rescuing his wife from Grey's unwelcome advances, Henry throws the bachelor from the train, and he and Evelyn decide to discard their fashionable behavior in favor of old-fashioned love.