When it comes to Christmas stories, one typically thinks of those that embody the spirit of the season, such as O. Henry's "The Gift of the Magi" and Charles Dickens's A Christmas Carol. The Yuletide-themed murder mystery is not usually the first thing that comes to mind. But in 1936, Mavis Doriel Hay wrote The Santa Klaus Murder, one of three detective novels she published in the 1930s. A classic country-house murder mystery, The...