After an afternoon spent in Munich, Ellen Theiss, a young student from a provincial college, does not return to the institute. Her lifeless body is found along the path through the woods that leads from the train station to the college. The news of his death caused panic among the companions: six months earlier, in fact, another girl had been murdered in similar circumstances. During the investigation, Derrick realizes that Ellen's death is to be connected to the crime that took place some time before and he devises a plan to frame the killer.

The lifeless body of the owner, Martha Balke, is found in a country house. For Derrick the case seems simple enough: the victim's husband, Alfred, inherits a great fortune with Martha's death and the man now also has the possibility of living with Roswitha, his young lover. Meanwhile, Marta's twin sister Johanna returns to Munich from the United States. When Derrick meets her he has an idea that could be helpful in framing the killer.

The 75th anniversary of the founding of a choir is celebrated in a hotel. At the party we sing, drink and dance. August Bark is also particularly cheerful and, during the evening, gives life to a provocative dance with the young and charming Irene Eppler. Shortly thereafter, the girl is found killed in her hotel room: she had a basal skull fracture. Chief Inspector Derrick begins to investigate trying to reconstruct the facts based on the testimony of those present. While it's not easy to identify the killer, Derrick has an idea as to who might be the culprit.

Helga Landau, a waitress in a small village tavern, returns one evening from Munich with the last bus of the day, the midnight one. She learned from her doctor that she was pregnant and wants to break the news to her young friend, Erich Holler, the son of the landlord where she works. A heated discussion arises between the two young people because Erich does not want to marry Helga and, on the contrary, tries to buy the girl's silence. The next morning Helga's lifeless body is fished out of a pond.

Along the metropolitan railway between Munich and Ottobrunn, the police find the body of a young woman, the third in a few weeks. Derrick and Harry suspect that the killer is acting on the edge of the railway line because it is someone who works in that environment. The investigations lead to a construction site of workers who have been working on the arrangement of the tracks for some time.

Elder Paul Seibach has been working as a security carrier for a supermarket for a year. One day, waiting for him at the exit, the man finds a masked thug who, after robbing him, manages to escape. Back home, Seibach shows up at the door of his neighbor, Harald Rohn, claiming to have recognized him as the perpetrator of the robbery. That same evening Derrick is called to the crime scene: Seibach's body lies on the road in front of the house and his children, Lena and Eugen, cannot explain their father's tragic death.

Paul Bubach, a charming middle-aged man, meets older women and convinces them to sell their belongings to move with him to the island of Madeira where they can spend a second youth. Inspector Derrick finds that this story presents an unclear point, however: neither of the women seduced by Bubach ever made it to Madeira, indeed both have disappeared without a trace. Even Kläre, Bubach's niece, cannot imagine that her beloved uncle could be a murderer. In the absence of any clues, Derrick is forced to wait for something to happen...

The lawyer Rieger is contacted by telephone and forced to hand over a gun to a dangerous prisoner, a certain Günter Hausmann, so that he can easily escape. The mysterious telephone operator warns Rieger that his wife has been taken hostage and will be killed if the request is not fulfilled. The lawyer agrees but, before delivering the weapon, he empties the magazine. A few days later Derrick is informed that Hausmann killed a prison guard during his escape.

Robert Hofer accidentally meets a man in whom he recognizes an old comrade in arms named Goldinger. The man, on the other hand, claims his name is Paddenberg. A short time later, the police found Robert Hofer's body in the Forstenrieder Wald, a forest on the outskirts of Munich. Chief Inspector Derrick investigates.

On a spring evening the young Annelise Röhrig is cycling home after attending a party. Along the way, she meets Richard Hoffmann, a neighbor and friend of the family, who, with his car, offers to accompany her by loading the bicycle in the trunk. The next morning, Inspector Derrick and his assistant Harry Klein receive a call: the body of a young woman was found in a landfill.

Dernberg is dead in his photo laboratory. Near the body, Inspector Derrick finds a piece of paper with the word "school" on it. An important clue as it turns out. A pastor suddenly appears with the desire to say a prayer for the murdered man. Derrick meets him again the next day—of all places—at his school, near the crime scene.

A bank robbery goes down on a peaceful Monday morning. A foolishly brave customer rips the mask off from one of the robbers, and is shot right after. Derrick recognizes the shooter from the surveillance tape.

A couple arrives home on a cab. Stepping out and preparing to pay the fare, they hear three gunshots. Sales consult Alfred Naujocks lies dead on the street.

Erich, a drug addicted burglar, enters a presumably unoccupied apartment in search for stuff to pawn. There isn't much to be stolen, but he finds a dead young lady in the bedroom.

Erich Schuster borrows keys to his old employer's office so that he could use the photocopier. But on the trip he runs to a situation. The Jeweler's shop in the same building is under burglary.

Herta Kolka has finished her guitar lesson. Shortly after she has left, her teacher hears gunshots and runs to the window to see her lie dead next to her car.

Gerhard Brosch has been defrauded in stock exchange speculation, and he has lost everything, including all property of his son and daughter.

Dr. Schenk has a problem. He must ask Derrick, who lives next door, to fetch some stuff from his home. He doesn't want to go himself because his wife's lover boy is there.

Jakob Lohbach, husband to a rich restaurant owner, dates one of the waitresses.

Something creepy is going on in the Weidau manor. Two young people are definitely murdered a couple days apart, but there's no apparent motive.

Arnold Bothe receives a severe head trauma and dies at the hospital. However he managed to drag himself to the phone and call for help.

Martin Theimer has capped the bottle. He has decided that he is the right man for an important role in a movie. Another actor has been selected, but Martin is insistent. All of the sudden, his path to stardom is open - but at a cost.

Dr. Kroll has been sentenced to an asylum for criminally insane for attempting to murder his wife. After years of therapy, his psychiatrist, Dr. Kraus is convinced that he is now mentally sane and able to live in the society again.

Werner has been released from prison. His son, now the headmaster of a popular school, refuses to deal with him.