In the middle of the freezing winter, a journalist is murdered in the northern Swedish town of Lulea. Crime reporter Annika Bengtzon suspects that the killing is linked to an attack against an air base in the late 60. Against the explicit orders of her boss, Annika continues her investigation of the death, which is soon followed by a series of shocking murders.

Annika quickly finds herself drawn into a spiral of terrorism and violence centered around a small communist group called The Beasts. Meanwhile, her marriage starts to slide, and in the end, she is not only determined to find out the truth, but also forced to question her own husband's honesty.