A series of death along with Danube lead Marc to think a crocodile is responsible, but is it really? During an autopsy Dr. Graf confirms that the latest victim did indeed drown. Still puzzled, Rex's finds some new evidence, which turns the case around.

Nina, a well-known radio presenter, is driving home one night when she hits and kills a pedestrian. She tells the police it was an accident, but Dr Graf discovers in the autopsy there is more to what happened then what Nina says.