Together with Commissioner Max Steiner, Inspector Felix Burger, and their boss Major Evelyn Leitner, German Shepherd Rex investigates cases in the Vienna homicide division, supported by pathologist Dr. Tom Wippler. For Max, Rex is more than just a four-legged colleague. He also shares his home with the German Shepherd. The experienced investigator is single and still suffering from his separation from his ex-wife Sarah. But things are about to get lively again when Max's adult daughter Anna returns from South America. And where the daughter is, the mother is never far away.