I have a soft spot for locked-room mysteries, and “Salvation of a Saint,” by Keigo Higashino, is a particularly clever entry in the genre. A man is found dead of poison in his Tokyo home. Every door and window – except one on the second floor that is too small for a human – was locked. The most likely suspect, the wife he just asked for a divorce, was hundreds of miles away at the time, and the victim prepared the coffee himself. No trace of the poison was found in the bottled water he preferred or the ground coffee in the refrigerator, and his lover used the same kettle that morning to make coffee for both of them.
“A detective who worried about hitting dead ends should consider a change of profession,” thinks the lead investigator, but they are nonetheless stumped. In this case, howdunit is such an enticing intellectual problem that it lures in physicist Manabu Yukawa, aka “Detective Galileo,” despite his vow to avoid further police entanglements. Readers who like an ingenious puzzle will enjoy pitting their intellect against Galileo's.