A light plane crashes outside of Mossby strand, and a detonated armour-piercing shell is found in the wreckage. Kurt Wallander is called in to investigate. A few days later, two elderly sisters are killed in an explosion in a sewing supplies shop. Traces of an advanced explosive are found in the burnt-out shop, and evidence soon mounts to indicate that both events are tied to a showdown between two rival narcotics gangs. By chance, Wallander makes a strange discovery about one of the suspects, which leads him back to a traumatic experience from his early days on the force. The continued investigation becomes an intense, violent struggle with Wallande.