On the hunt for a killer who collects hearts BKA specialist Tom Bachmann is at an international conference in Belgium when hikers report a body found in the High Fens. Her dog has led her to the bat cave, where the gruesome sight of the mutilated corpses shocks her deeply. Bachmann and his BKA team are asked by the local authorities for administrative assistance. The hearts of the dead were torn out. And while Bachmann creates the profile of the killer, he addresses his next victim.