Dirk Valentine's treasure is the lost riches of a famous southwestern outlaw.
In 1883, the outlaw Dirk Valentine hid solid gold hearts in a simple wooden chest within the Anasazi cliff dwellings near the town of Dry Creek for his beloved girlfriend, Frances Humber, to find. He loved creating puzzles for her to solve because the expression on her face when she was focusing hard on something was especially beautiful to him.
Unfortunately, her father, the sheriff, managed to arrest Dirk and intercept the letter he sent to Frances from jail that contained the first clue to finding the treasure. Although Dirk promised Frances in the letter that he would escape, he was hanged nine days after his arrest. A heartbroken Frances left Arizona and never returned. 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.