The murder in Hercule Poirot’s Christmas (aka, A Holiday for Murder and Murder for Christmas) happens on Christmas Eve in a locked room. The mystery was first published in 1938 in England and Dodd, Mead published it in the U. S. in 1939. Christie was at the height of her powers and this puzzle is clever. A wealthy, dying man calls his sons and their wives together for a “holiday” party. But when the father announces he’s going to change his Will, multiple motives spring up. When the body is found, Hercule Poirot investigates and finds a tangled web of lies. Herclule Poirot’s Christmas is one of the best Poirots I’ve read. If you’re looking for a dandy holiday mystery, you’ll find it here.