In 1883, the outlaw Dirk Valentine hid solid gold hearts in a simple wooden chest within Anasazi cliff dwellings in Arizona for his beloved girlfriend, Frances Humber, to find. Her father, the sheriff, intercepted the letter he wrote that contained the first clue, however. Dirk was caught by her father and hanged soon after, and a heartbroken Frances left Arizona for the rest of her life. She never found the treasure, writing to her cousin Ellie that she was "too heartsick to care" about finding it.
Nancy finally discovers the treasure in a room locked with several rusty keys, all hidden in pots all around the cliff dwellings. When she opens the door, she sees a room with wine goblets, a "V" written with gold lumps and a "V" painted on the wall, indicating that Dirk probably wanted to surprise Frances by being there when she finally found it and celebrate with her.