Case of the Fiery Fingers, Perry Mason Mystery, Pocket Books 1957 prntg.

Poker-faced Nellie Conway, the nurses bed-ridden Elizabeth Bain, brings trouble when she calls on Perry Mason with a glass phial containing four pills which she suspects are poison. Her employer, Nathan Bain, she says, had promised her money to give them to his wife. But when Mason has one of the pills analyzed it is found to consist of acetylsalicylic—in other words good old-fashioned aspirin. Is Perry Mason’s client a hoaxer, a psychopath, or something trickier? Nathan Bain’s next move is to accuse Nellie of theft and provide proof by shining ultra-violet light on her fingers. The case which began like a joke suddenly becomes sinister. Perry gets his client out of this spot but trails her to New Orleans where he has a hard job disentangling fact from theory on the subject of Mrs. Bain. One flying trip to New Orleans. One charge of vagrancy--against Perry Mason. Plus two dramatic courtroom scenes climaxed by one of the most spectacular grandstand plays of Mason's distinguished career--add up to Grade-A mystery fare