A worker at a transportation company is found dead after going through a window. Moser must investigate to find out whether it was murder or suicide.

Rex, still depressed about Moser's death, finds himself being passed from Böck to Höllerer. A corpse in the river is found but has no identification. A passerby spots a bag, and it proves to contain the only evidence in the case. Alexander Brandtner is called in to replace Moser, having lost his own dog Alex goes to see Rex and together a new partnership is formed.