Little Ines is found dead on the banks of the Danube. At the same time, girls disappear from an amusement park, but a few days later they are found again: abused and in such shock that they are unable to be interrogated. Inspector Moser suspects a connection between the murder and the kidnappings. The way to the perpetrators leads over the little Birgit. The child has been in a clinic since the kidnapping and is unresponsive. Rex stays in the hospital for days, trying to pull the child out of his apathy. While the dog slowly finds access to Birgit, Commissioner Moser and his team investigate unsuccessfully in the amusement park. Then Rex and Birgit disappear. In the stress of the investigation, Commissioner Moser also has to find a home for himself and Rex. He meets an attractive veterinarian...

An unknown man apparently threw himself in front of a train and was run over. However, coroner Dr. Graf does not believe in suicide, and when Moser and Rex find suspicious traces near the railway embankment, it is clear: The man was already dead before the accident. Neither the wife of the dead Gerti nor his lover Irene can show an alibi. Only when Kunert, the mechanic of an illegal car repair shop, finds traces of blood on the expensive car of the young Alexander Prince does Moser track down the criminal. But the arrest is thwarted, the perpetrator can flee...

In the middle of the nudist area of the Danube floodplains, a couple is murdered. On the chest of the dead is a bloody mark. Is it a crime of jealousy or a ritual murder? A similar murder a year earlier could never be solved – now the "love couple murderer" has apparently struck again. Stockinger investigates at the scene and finds a suspect, but cannot prove anything to him. Inspector Moser, together with his colleague Elisabeth Böhm, decides to set a trap for the murderer: On the nudist grounds, the two disguise themselves as lovers. Rex hides nearby to warn her in time. A hot night begins...

A German tourist photographs young men in Vienna's city centre. One of them, the handsome Hubert Meixner, he invites to his hotel room in the evening. The next morning, the tourist is found dead – the photos are the only trace. When Hubert Meixner wants to pick up the pictures, he is followed by Commissioner Moser and Rex. But he has a watertight alibi for the time of the crime. Only one can help: Max Koch. While he investigates undercover with Rex, Moser and Stockinger examine the photos. The trail leads to the Volksgarten. With Rex's help, Moser comes to the connection between the photos and the motive for the crime. Also privately there is some excitement: Moser and Rex move into the new house and Moser makes an appointment with the veterinarian Dr. Koller. Rex doesn't like that at all...

n the cabin of a beauty salon, a customer suffocates. An employee has previously observed how an unknown person has left the cabin of the dead. The best friend of the dead, sparkling wine manufacturer Karla Wilke, is in the neighboring cabin at the time of the crime. Coroner Dr. Graf confirms Richie's suspicions: The customer was murdered. While Moser interrogates Karla Wilke, Rex escapes an assassination attempt at the last second. Suddenly, lawyer Dr. Rudolf Baumann appears. The attractive Baumann is not only Mrs. Wilke's lover, but he also had an affair with the dead. His alibi for the time of the crime is not verifiable. Moser tracks down the perpetrator, he is sure: The murderer has made a serious mistake, he has confused his victim. Mrs. Wilke's life is in danger...

In a hotel room, a man is shot dead and the blind telephone operator Brigitte Heinrich is an earwitness to the murder. A safe key brings Commissioner Moser and his team on the motive for the crime: The dead man was on the trail of toxic waste pushers. Moser's and Stockinger's investigations lead to Slovakia, Rex stays behind with Brigitte Heinrich. But the two are in mortal danger: sophisticated murder attempts are made on the blind witness. Only Rex can protect them – in vain, but they are still lured into a trap. The unscrupulous gangsters have too much to lose and therefore stop at nothing...

Ernst Fuchs and Fritz Groh attack a money transport. In the violent exchange of fire with the guards, Fritz and a money messenger are killed – Ernst flees with the money. Commissioner Moser and his team take up the persecution. During the hunt through a winding social building, Moser and Rex drive the fugitive into a corner: Fuchs goes crazy and takes a hostage. Commissioner and perpetrator know each other: There is still a score to settle between the two. When Fox flees into an old water tower, a dramatic shootout ensues, in which Rex unexpectedly intervenes...

In the middle of winter, little Sabine is found dead in an outdoor pool. Coroner Dr. Graf confirms Moser's suspicion: It was not an accident, the location is not identical to the crime scene. The child was killed in another bath. In the changing rooms, Rex finds a trace: Sabine's wallet. With his help, Moser wants to lure the perpetrator into a trap. And indeed, after a long nightly wait, a man enters the swimming pool. But he has an alibi for the time of the crime. However, another suspect confesses to the murder shortly afterwards – the case seems closed. But Moser still has doubts and continues to investigate. Then Rex finds another child on the grounds of the swimming pool – buried, but still alive. Rex is on his own...

On the outskirts of Vienna, four women's bodies are found – buried strictly geometrically at a distance of 666 meters from each other. Everything points to a ritual murder. For Rex and Moser, a race against time begins: Who will be the next victim? The trail leads to a remote castle, the headquarters of a sect. There, Moser and his colleagues initially search in vain for clues: the work is hindered by cult members. But Moser is able to cleverly evade his watchdogs and discovers Anne, a young woman who is to be consecrated to Satan. At the last minute, Anne escapes from the sacrificial ritual at Moser's house. But she knows too much: the persecutors don't let up. But not only Moser and Anne are trapped, Moser's girlfriend Sonja is also threatened. Then Rex intervenes – a life-and-death battle begins...

A young, pretty woman is strangled in the bathroom. Rex is sensitive to the smell on the belt of the bathrobe. But apart from the perfume, the perpetrator has left no traces. Commissioner Moser and his colleagues find out that the woman met an attractive man before her death. Everything points to a marriage swindler. But does a marriage swindler kill his victims? Then the young Silvia Lorenz commits a spectacular suicide attempt. With a ruse, Moser comes to the connection between the murder and the suicide attempt. But the suspect has an alibi. The investigating magistrate cannot issue an arrest warrant due to lack of evidence. Only one can help: Rex...

When the industrialist Erich Staller is kidnapped, the police initially learn nothing despite ransom demands in the millions, because the perpetrators threaten to kill their victim. Shortly thereafter, the body of pensioner Franz Pichler is discovered in an empty railway carriage. Richie Moser and his team find the clue to the crime scene: a garden house on the outskirts of the city – prepared as a prison. Meanwhile, Staller tries to provoke his kidnappers so that he can identify them. During a routine interrogation in connection with the pensioner murder, Moser meets Heidi Staller, the wife of the kidnapped, but she refuses to cooperate. During their surveillance, Rex intervenes and the kidnapped provides a life-threatening surprise...

Dr. Heinz Hausner, Professor of Veterinary Medicine, collapses dead on the street: heart attack. What at first looks like a natural death is murder. Dr. Hausner's wife Ines and his lover Uschi Reichert were near the crime scene – neither has an alibi. Meanwhile, a beagle that Hausner examined shortly before his death disappears from the cages of the university. Rex tracks down the distraught dog lady... Richie has chosen Sonja, although Rex is against it. But the pretty veterinarian searches in vain for an undisturbed conversation. Something is constantly coming up. When Moser finally has time for her, it's too late...

When the owner of two vegetable shops at the Naschmarkt is shot, the investigation is obstructed by the market people. Shortly afterwards, a truck driver is killed in the same market: The dead man, Werner Gredl, is the husband of the Russian landlady Irina. Inspector Moser disguises himself as an unskilled worker and investigates undercover at the vegetable market. He realizes that Irina is afraid: she is being blackmailed. In his undercover investigations, Moser tracks down a dubious group. The encounter with the people becomes life-threatening for him and Irina. Only Rex can prevent disaster...

A car crashes over a slope, the driver burns beyond recognition. A fire expert alerts Commissioner Moser and his team: There are inconsistencies in the course of the accident. Rex finds clues that point to a crime – the woman was still alive when the car caught fire. Accident, suicide or murder? The trail leads to the red light district. While Moser and Dr. Graf reconstruct the face of the dead with the help of a computer program, Stockinger and Rex follow the trail of two missing prostitutes in relevant establishments... Because Stockinger is conspicuously scattered in the office, Moser and Höllerer confront him. He hesitantly reports that his wife Karin has inherited her father's dental practice in Salzburg. Stockinger asks for his transfer to the Salzkammergut...

The mood in the office is depressed because Stockinger's departure to Salzburg is imminent, when two women's corpses with their throats cut are discovered in quick succession: a judge and a doctor. The team is feverishly investigating because the perpetrator is likely to strike again. His motive: revenge. Then Rex finds another victim of the gunman. A dramatic chase begins and ends in a kindergarten. Meanwhile, Höllerer is preparing a small celebration in the office: with sausage rolls and farewell photo...