The Wild One (Peter Ash 5) by Nick Petrie
Struggling with PTSD, veteran Peter Ash has no intention of getting on an airplane - until a grieving woman asks him to find her grandson. The woman's daughter has been murdered. Her husband Erik is the sole suspect. Finding the boy becomes more complicated when Peter is met at the airport by a man from the US Embassy. For unknown reasons Peter's own government doesn't want him in Iceland, and when he refuses to leave they start hunting him. Now Peter must confront his PTSD and amidst a powerful Icelandic snowstorm, find a killer, save a child, and keep himself out of prison.