An old tanker veers off course, heading straight for the Øresund Bridge, the scene of the now-infamous crime that first united detectives Saga Norén (Sofia Helin) and Martin Rohde (Kim Bodnia). The Malmö Coast Guard urgently contacts the tanker but there is no reply, the call just echoes eerily across the bridge of the ship. When the Coast Guard finally board the ship they discover there is no crew present but find three Swedish and two Danish youths chained below deck. Saga Norén of Malmö County Police is immediately put in charge of the case but, as Danish victims are involved, she contacts her previous case-collaborator, Martin Rohde, and they embark on investigating the mysterious and complex case.