A strange smell irritates the chairman of the model railway club in Crailsheim. The cause is quickly discovered. In the floor of the club's premises, the railway enthusiasts find the body of their club member Fritz Klingler - dismembered and packed in garbage bags. Criminal investigators Lisa Luft and Heiko Wüst quickly find out that the murder victim was rather questionable in his humanity. His daughter Viola and his ex-wife have completely severed ties with him. Additionally, Klingler, as a TÜV inspector and a notorious pedant, had made many enemies.