Vacationing at her friend Laura's horse farm, Nancy must outwit a saboteur who poisons the stock feed and then steals Laura's favorite horse, and Nancy finds suspects in a spoiled rival and a band of animal activists.

Teenage detective Nancy Drew uses her courage and powers of deduction to solve the mysterious happenings in an old stone mansion. She recieved a phone call from her friend, Helen Corning. Helen says they were robbed, heard thumps in the night, and have heard strange music when no one has turned on the radio Helen begs Nancy to come to Twin Elms and try to solve the mystery.

While staying at a ranch in Arizona, Nancy Drew becomes involved in a mystery surrounding a mistreated child.

Nancy uses a lost diary to exonerate an innocent prisoner.

A puzzling message attached to the leg of a wounded homing pigeon involves Nancy in a dangerous mission.

The original version - Nancy wins some land in Canada and problems develop when it is believed that there is gold on Nancy's property. Also a subplot about long-lost lovers.

Nancy and her friends establish headquarters in a seaside yacht club to investigate strange happenings in a book store and the disappearance of a marble statue.

Nancy Drew tries to find a clue to the strange tapping sounds in the house of a retired actress.

Nancy Drew sets out to prove that her father's client was unjustly accused of trying to sabotage the United States space program.

A search for stolen jewelry takes Nancy to New Orleans where she uncovers a swindling racket in which a medium uses her trade to relieve victims of their valuables.