At the B&N Reads blog he tagged six of the more unputdownable locked-room mysteries ever written, including:
The King is Dead, by Ellery QueenRead about the other entries on the list.
Ellery Queen was for a time the most famous fictional detective (and literary pseudonym) in the world, and this classic novel is a prime example of him at his best. A man makes a public threat that he will shoot his father at midnight; his father retreats to a secure room alone with his wife, while Queen, hired on, sits in another location with the son, who has an unloaded weapon. At midnight the son raises the empty gun and pulls the trigger—and the father is shot dead, seemingly impossibly. Queen eventually gets to the bottom of it, and the novels were always presented as a fair-play “challenge to the reader,” stating that all the clues necessary to solve the mystery were in the story, and if you paused before reading the explanation you would have a fair chance of figuring it out.
--Marshal Zeringue