After a double murder sends shock waves through a quiet Swedish town, lead detective John promises the grieving families that he will find the killer.

As weeks turn into years without answers and his home life slowly falls apart, a desperate John turns to an unlikely ally to help crack the case.

John and Per's investigative efforts are obstructed by their clashing personalities. A prying journalist adds to the pressure.

With everyone nearing the ends of their ropes, a revelation from an unexpected source leads to a breakthrough in the case.