The young earl of Carnavon travels to America in search of his ideal, and on the observation platform of the limited his quest abruptly ends. The girl is beautiful but rather distant. The Earl bluntly declares that he would do anything to win her regard, -to know her better. The girl laughs enigmatically and names the Vantine necklace, mentioned in the newspaper, as the price of her friendship. Then she disappears inside her compartment. That night at the club the Earl is introduced to John Vantine, whose name he recognizes. The Englishman resolves to dare all and become a thief for the unknown girl of his dreams. He jimmies his way into the Vantine mansion, makes his way to the library, and is promptly apprehended by the master of the household. Vantine recognizes the Earl and is shocked to discover his crookedness. The Earl makes a clean breast of it, however, and tells him how it all came about. Vantine is indulgent and rather admires the young fellow's daring, since he is convinced of the Earl's intention to restore the jewel once the mysterious girl's name is learned. Returning from the opera, the Vantine limousine stops at the door and a young woman alights. It is Miss Sylvia Vantine, the bewitching heroine of the Earl's railway adventure. She is wearing the necklace, but in a moment it is unfastened and she drops it to the floor. The Earl recovers it and presents the string of jewels with a low bow. After that it's easy.
—Moving Picture World synopsis