A Midsummer's Equation by
Keigo Higashino
(A Detective Galileo Mystery)
Manabu Yukawa, the physicist known as "Detective Galileo," has traveled to Hari Cove, a once-popular summer resort town that has fallen on hard times. He is there to speak at a conference on a planned underwater mining operation, which has sharply divided the town.
The night after the tense panel discussion, one of the resort's guests is found dead on the seashore at the base of the local cliffs. The local police at first believe it was a simple accident-that he wandered over the edge while walking on unfamiliar territory in the middle of the night. But when they discover that the victim was a former policeman and that the cause of death was carbon monoxide poisoning, they begin to suspect he was murdered