A wolf has been roaming the forests around Lake Constance for some time now, calling hunters and animal rights activists alike to the scene. When forestry worker Oliver Schlösser (Robert Stadlober) finds a dead hunter impaled in an old wolf trap detectives Micha Oberländer (Matthias Koeberlin) and Hannah Zeiler (Nora Waldstätten) are called to the crime scene.
They interrogate Melanie Bodenbach (Cornelia Gröschel), in whose nearby guesthouse the hunter stayed overnight, but who claims to have known nothing about his plans.
Instead, the detectives catch Melanie's son Timmy (Jeremy Miliker) taking off with the laptop of the murdered man.
Animal rights activist Pit Adams (Jonathan Lade), who, like Timmy's grandmother Ruth (Elfriede Schüsseleder), is campaigning for the protection of the wolf, also becomes a suspect.
Everyone seems to be connected to everything else, but who is wolf and who is just a lamb? In order to solve the case, Zeiler and Oberländer have to dig deep.