The Bird with the Broken Wing — Agatha Christie

Previously published in the print anthology The Mysterious Mr. Quin.

While staying with the Keeleys at their country house, Mr. Satterthwaite happens to be in the library while the younger guests are holding a séance. Among the nonsensical messages are two clear ones: “Quin” and “Laidell.” Before long, there is a tragic death in the house, and Satterthwaite, with a little help from Mr. Quin, correctly determines that it wasn't suicide, but murder!