Anthony Gethryn, ex-secret service agent, is an occasional "special correspondent" for a weekly newspaper and is assigned to cover the story when a cabinet minister, John Hoode, is found murdered in the library at his country house, battered to death with a wood-rasp.

Gethryn recalls his acquaintance with a member of the household and is thus invited to investigate the crime as a kind of "friend of the family".

The focus on the breaking of an elaborate alibi is similar to the work of Freeman Wills Crofts, MacDonald's contemporary.

"[1] The story was made into a film with a screenplay by Philip MacDonald which was directed by Michael Powell in 1932.

In a contemporary review, Kine Weekly called it "an ingenious murder mystery.