Family affairs and incessant rain bring Chief Superintendent Littlejohn, of Scotland Yard, to the county town of Roswalton and whilst he is there a series of deaths, with no apparent connection, agitates the place.

The victims are a motley lot: a Canon of the Church, a Brigadier of the Army, a very distant and aged relation of Mrs. Littlejohn called Cousin Pentstemon; and a mysterious nobody whose dead body is found murdered in six inches of water on a fair-ground.

It there are any more done-in, there be a panic, says the local superintendent.

Eventually, Littlejohn sends for his colleague, Superintendent Cromwell. And together they sort out the affair and are glad to leave the place.