The Tschugger Bax Schmidhalter from the Valais wants to hunt down local drug dealers. To do so, he sends the shy trainee Smetterling on a daring undercover operation. It goes wrong.

A confrontation on the Simplon escalates and shots are fired. Possible victim: the trainee Smetterling, who has disappeared without a trace. Bax makes his mark with a primary school class. Instead of teaching road behaviour, he tells cool cop stories. Fun could turn into bloody seriousness.

A bloodbath on the Simplon Pass prompts a large-scale police operation in the Valais. The Tschugger Bax, who is forced to do cleaning work, secretly goes on the hunt for criminals and hits on federal police officer Annette. Killer Mirko searches for a mysterious tomato sauce. No one can stop him.

Bax is looking for the killer because he has already made a witness disappear. In addition, the Tschugger wants to convict the crook couple Juni and Valmira in a spectacular interrogation. And Fedpol officer Annette now knows what happened in the Pfynwald. This means the end of Bax's career.

Bax is betrayed by someone close to him who is himself involved in criminal activities. Valmira's dream of becoming a hip-hop star could come true. Smetterling awakens from his coma and is already in mortal danger again. And Juni makes a spectacular find.

Bax and Pirmin track a killer to the Christ Roi statue high above the Rohne valley where they witness a strange ceremony of a sect. Valmira becomes the target of mole Gerda and Juni comes to the Tschuggerposten with a mysterious key.

Bax is on the run from his own colleagues. Alone with his mother, he persuades intern Smetterling to commit a burglary in order to exonerate himself. Valmira has been kidnapped and the kidnappers demand the DVX key from Juni, otherwise Valmira will die.

Bax and Smetterling find the decisive clue to the plans of the sect. Apparently, the cult wants to blow up the Grande-Dixence dam and flood the entire Valais region. Valmira doesn't let her kidnappers get her down and Biffiger's curiosity puts him in mortal danger.

The police believe that Pirmin murdered his father-in-law. Gerda, the actual perpetrator, wants to get the explosive key from Bax - no matter what the cost. Bax is handcuffed and cannot defend himself and Valmira is in mortal danger.

Bax and Pirmin cannot prevent the countdown to the explosion of the dam wall. With the latest technology, huge guns and a superhuman effort, the Tschuggers try to stop the catastrophe. Will they save the Valais from the end of the world?

Bax needs to take a break from Valais and therefore decides to open a smoothie kiosk in Bern. Pirmin, now a full-time father, is instead following a case of murder disguised as suicide, while Valmira is on the verge of breaking through, but the catch is around the corner.

Pirmin's investigation turns out to be a complete failure. Bax is in fact too busy saving his colleague Julie from a love scam and also has to face an unexpected tragedy. Meanwhile, Fricker, now bankrupt, causes one of his workers to fall into a deadly trap.

Bax is suspected of murder, but during a prisoner transport he manages to escape together with Juni. The two thus end up in an uninhabited region, finding themselves without water and without escape. For his part, Pirmin instead has to get rid of a corpse, while Valmira realizes that she has been deceived.

Bax and his gang come across Smetterling in the Pfyn woods, where he is hiding and is busy hunting down mafiosi. When the criminals show up, the time of reckoning finally arrives. What the cops don't know, however, is that the criminals have Valmira in their grip.

Valmira lures the mafiosi into an ambush with fatal consequences, while to get to the bottom of a double murder the cops infiltrate the heart of the Swiss secret services. Despite constantly having two Romande policemen on his tail, Pirmin's son will prove fundamental in solving the case.