The Dry - Jane Harper

The tiny rural town of Kiwerra hasn't seen rain for two years. The drought has ravaged the town, coupled with the blistering heat that's becoming more unbearable by the day; tensions are at a breaking point for the whole town.

When his childhood best friend, Luke, seemingly snaps and murders his wife and little boy before turning his gun on himself, Aaron Falk returns to his hometown to attend the funeral - only to find out you can never really escape your past, even after twenty years. 

At the insistence of Luke's parents, Aaron joins forces with the local police to investigate the deaths and uncover the truth... As they dig deeper, the townspeople get increasingly unwelcoming, and a trail of secrets and lies is revealed - forcing Aaron to confront painful memories from the past, including the secret he shared with Luke involving a decades old mystery.

Did Luke really snap, or were the murders at the hands of someone else? Did the secret have anything to do with it - or is someone trying to make it look that way to derail the investigation? And if he really was the culprit, why was his baby girl left alive?