Mrs Murphy's Underpants(1963)
(The seventh book in the Ed and Am Hunter series)
A novel by Fredric Brown
"Who put the Benzedrine in Mrs. Murphy's Ovaltine?" Brown's nephew-uncle team of gumshoes, Ed and Am Hunter, make their final book-length appearance as they try to untangle a murder plot against a Chicago horse-racing scion.
Used availability for Fredric Brown's Mrs Murphy's Underpants