The Secret of Saint Olaf’s Church

Inspired by 15th-century court records, Hargla’s diverting if unfocused debut introduces nosy Estonian apothecary-turned-detective Melchior Wakenstede. In 1409 Tallinn, Estonia, fearsome Commander Clingenstain, a knight of the Teutonic Order, drunkenly returns to his rooms in the Toompea castle, where an assailant decapitates him and puts a coin in his mouth. Teutonic officials call on Melchior, a divisive figure in Tallinn who’s nonetheless respected for his scientific wisdom, to help them investigate. The motive initially seems to be revenge from one of Clingenstain’s many enemies, but more murders follow, and red herrings abound. Melchior draws on witness accounts, his knowledge of poisons, and some rather flimsy clues (including the positions of chess pieces left on a board) to solve the mysteries, then brings the town together and identifies the culprits as theatrically as Hercule Poirot ever did. The story’s medieval trappings—castles, knights, squires, elixirs, lute players, and battle axes—provide a rich atmosphere, but the tone veers uneasily from gentle cozy to rigorous historical to steamy suspense, courtesy of a few explicit sex scenes. It’s a valiant effort, but the muddled mood keeps this from soaring. (Apr.)