When the customers of the River Heights pharmacy take seriously ill after being delivered their medicine, Nancy is convinced that sabotage is involved and searches for the deadly drug.

Two customers have fallen ill, and a third has died after receiving deliveries from the local pharmacy. Nancy sets out to find out who is behind this case of sabotage.

After Nancy's friend George takes a job delivering prescriptions at the local pharmacy two customers become ill, and a third has died. As Nancy begins her investigation she receives her own prescription filled with danger.

Nancy faces a bitter foe in pursuit of a venomous villain. #127

A two-hundred-old mystery puts Nancy in immediate peril.

Nancy and Bess start hunting for an elusive suspect to save the Pennington Estate. Nancy's best lead comes from someone who wants to remain anonymous.

When Matilda Benson solicits the help of Perry Mason, her request seems simple enough: cruise to a gambling ship moored just beyond the twelve-mile limit and buy back the IOUs signed by Miss Benson's niece. But after Mason reaches the floating casino, he discovers problems aplenty -- most notably the ship's owner with a bullet hole through his head. Strangely enough, Matilda and her niece are also on board that night . . . when someone tosses a gun over the railing. Does Perry Mason's client have something to hide?