The Dragon Man — Garry Disher

Meet Hal Challis, Detective for the Mornington Peninsula police force in Southeast Australia, in the first investigation in this prize-winning crime series
 
A serial killer is on the loose in a small coastal town near Melbourne, Australia. Detective Inspector Hal Challis and his team must apprehend him before he strikes again. But first, Challis has to contend with the editor of a local newspaper who undermines his investigation at every turn, and with his wife, who attempts to resurrect their marriage through long-distance phone calls from a sanitarium, where she has been committed for the past eight years for attempted murder -- his.