"... and not least foul among these night-monsters (which may be found even in our pleasant land of France) is a certain shape of evil hue which by day may not be recognized, inasmuch as it may be a man of favoured looks, or a fair and smiling woman; but by night becomes a misshapen beast with blood-bedabbled claws. So I say to you, even you who live in the city of Paris, when your fire burns low by night, and you hear a gentle tapping of fingers at the window-pane, do not open your door to this supposed traveller, who..."

Thus begins It Walks by Night, the first of more than 70 novels by Carr. Henri Bencolin was first seen in some of Carr's college stories published in the school newspaper, The Haverfordian. Seen in only five novels, Bencolin last appears in 1937's The Four False Weapons.

With his first novel Carr laid claim to a subgenre of mystery fiction, the "Locked Room" mystery. By the end of his writing career Carr, in addition to being a pioneer of historical mysteries, had become the undisputed master of the Locked Room.

All of the American editions of the Bencolin novels were published by Harper & Brothers as was the first British Bencolin novel. The British edition of the third Bencolin novel was not officially published until 1976 by Svern House. The British edition of the three remaining Bencolin novels were published by Hamish Hamilton.

If the title is in Red then the US edition is NOT the true first edition.

The Four False Weapons (1945)