The Last Darkness — Campbell Armstrong

Detective-Sergeant Lou Perlman takes center stage in the investigation of a hanged man that leads him on a twisted trail through Glasgow in international bestselling author Campbell Armstrong's suspenseful crime novel

Amid Glasgow's icy streets and Christmas decorations, a well-dressed businessman kills himself in a most public manner -- hanging himself from Central Station Bridge. When it appears that the dead entrepreneur somehow dragged himself up that bridge, suicide is ruled out, and murder takes the lead.
 
As Lou Perlman investigates the hanged man, something about the corpse reminds him of his childhood in the crime-ridden Gorbals section of the city. As one death follows another, his hunt for the killer takes him into dangerous territory.
 
Glasgow's wintry streets shimmer with menace in this top-notch thriller about a good cop with a few too many secrets.

The Last Darkness is the 2nd book in the Glasgow Novels, but you may enjoy reading the series in any order.