In the Leipzig Civil Engineering Office, the cleaning staff Elina Jungklaus caught a burglar in the act. Shortly thereafter, the investigators arrive at the scene: The young woman is dead. Elinas shift leader, Peter Hassmann, had still tried to stop the burglar. But without success. The investigators are surprised because a trail leads to Oliver Jungklaus, the husband of the dead woman. He had copied Elina's key for work and sold it to Pedro Basker, who had broken into it.