In the midst of the worst crisis of his life, forensic scientist Kari Sorjonen gets to solve a hate crime that shakes the whole country. Underneath the railway bridge is a blood-painted "Make the World a Better Place" mural, decorated with the face of Sorjonen's arch-enemy, serial killer Lasse Maasalo. Sorjonen notices that his old methods are not enough to solve this tangle of crimes.