A girl named Gabi is searching for her sister Kristina at night using the tracker on her phone. The signal leads her into the forest, where an unknown man begins to chase her. Gabi manages to escape, but the man finds out where she lives by watching a video on Kristina's phone.

Lieutenant Colonel Karpov decides to dismiss Chagin. Shortly afterward, a mutilated female body is found in the forest. Zhuk asks to be assigned to the investigation, as he suspects the body belongs to Kristina, who went missing the day before. Moreover, the deceased wife of Igor had worked on a similar case, and her findings could be useful. He visits Vlad, the brother of his late wife, and confesses that he blames himself for Olga’s death—she had called him on the day she died, wanting to reveal the killer’s identity, but he was in a meeting and didn’t take the call. He also makes it clear that it’s important to him to be the one who catches the killer first.

Chagin comes to Zhuk with a proposal: he will tell him everything he knows about the missing girl’s case in exchange for Zhuk closing the case against Ilyin. At first, Igor refuses to even listen to him, but when Yevgeny mentions a similar body he saw a year ago, Zhuk decides to hear him out. He then tries to call Gabi, but is informed that she hasn’t been in touch for three days.

A PR specialist meets with Gleb to gather information for her feature article dedicated to the 20th anniversary of the military operations in the Caucasus, in which he was directly involved. Meanwhile, Gabi manages to free her hands using a shard of a plate and escapes the room where she was held captive—but her path to freedom is blocked by a new door...

Zhuk is told he must hand the case over to another investigator, confirming his suspicion that someone wants it buried. He asks his boss to delay the transfer, at least out of respect for his late wife, arguing that Kungur was framed. He also requests a meeting with Zeldin. Meanwhile, Karpov meets with surviving members of his recon unit from the Caucasus mission 20 years ago, including Gleb. Zhuk convinces Zoia Shentis’s husband to let him question her. When asked about Lentulov and Khmelevsky, she denies knowing them, but Zhuk presents evidence of contact. Her husband demands answers, and she admits to posing as Nika Bolshova’s friend and Larisa’s cousin. Furious, he kicks her out and agrees to withdraw his complaint against Chagin in exchange for Zhuk’s silence about the conversation.

Khmelevsky is wired for surveillance and sent to meet with Artur Lentulov to lure him into revealing information about Kristina’s death. He baits Lentulov with a claim about Kristina’s laptop, which investigators had shown interest in, and demands money for it—giving him one day to decide. After Khmelevsky leaves, Lentulov calls a woman, who later returns the call and says her “courier” will deal with Khmelevsky. She only needs Lentulov to pass on info about Max. Lentulov then calls Chagin and arranges a meeting. In person, he asks Chagin to arrive at the meeting spot with the “courier” ahead of time and check for police surveillance. Meanwhile, Zhuk places Khmelevsky under house arrest and assigns him a guard. Zhuk sets up surveillance on Lentulov. Chagin checks the meeting location and claims it’s clear. But no one shows up to meet Lentulov, because the “courier,” revealed to be Gleb, spots the surveillance and backs off.

Chagin informs Zhuk that Khmelevsky has escaped. They suspect he might be hiding at his parents’ dacha and head there. Maxim’s father reacts with hostility, but his mother is moved by Zhuk’s warning about the danger her son is in. She asks them to wait by the store, where she can speak to them discreetly. Meanwhile, Gleb returns to Lentulov’s apartment in search of the laptop. A photo found in an envelope reveals his next target: Liza Krapivina, Khmelevsky’s friend.

Chagin establishes contact with Nora, Solovyov’s assistant and lover. Meanwhile, despite being injured, Zhuk is eager to get back in action. He signs a hospital discharge refusal and asks Chagin to pick him up. On the way, he asks about Nora—Yevgeny admits she’s hard to reach and they still don’t know who she works for, although her phone is now being tapped. Zhuk manages to narrow down the forest area where the remaining girls' bodies might be buried. He insists the search must begin immediately to preserve any DNA evidence. Unbeknownst to them, Gleb is eavesdropping on their conversation with Karpov…

During one of Gleb’s visits, Gabi provokes him into turning off the basement camera. She’s planning another escape attempt, having secretly taken a nail file from the bathroom. Zhuk manages to track Gleb’s car via surveillance footage, but it has no license plates. Meanwhile, Nora calls Chagin and invites him on a date that evening, while Yevgeny meets with the husband of the late Nika Bolshunova. The man identifies Solovyov’s lawyer in a photo—he had given Nika a ride shortly before her disappearance. It becomes clear that Eduard had ties to each of the murdered girls. Chagin suggests arresting him and forcing a confession. Karpov spends the entire day reviewing office surveillance footage. Eventually, he realizes it was Gleb who planted the bug. On top of that, a sketch made by a paramedic after Lentulov’s murder closely resembles Gleb.

The police discover Karpov’s dead body—his car apparently crashed off a bridge. Worse, a decapitated female body is found in the trunk. Zhuk is convinced Karpov was framed, likely by someone on the inside, while his superior, Gorsky, believes otherwise. Gorsky orders Igor to close the case and pin the string of murders on Karpov. Igor refuses, despite knowing it could harm his career prospects. Meanwhile, Solovyov’s hacker discovers that Nora’s phone contains a cloned SIM card. Solovyov still believes she was unaware of this and assigns Gleb one final task: to kill Chagin. Zhuk has already been removed from the case, so no one stands in their way.

Chagin survives the explosion, while Nora looks for ways to quickly obtain foreign travel documents. Later, Yevgeny informs Zhuk about Filippov and reveals that it was Nora’s call that saved his life. They decide to act through her, though she clearly has no interest in meeting with him. The forensic expert has a change of heart and tells Zhuk the truth: traces of a sedative were found in Karpov’s blood, making it impossible for him to have driven the car himself. She also admits to being pressured by Gorsky and confirms his suspicions. Zhuk reports his concerns about Gleb Filippov to Feoktistov, who takes his claims seriously. He brings Vlad Litvinov onto the case and asks Zhuk to coordinate any further actions involving Gleb through him.

Gabi's escape attempt fails—Gleb catches her and locks her back in the basement. However, she manages to keep a phone she had slipped into her pocket. She records a voice message for Chagin but can’t send it due to no signal. Meanwhile, Nora arrives at a country house where Chagin is already waiting. She tells him about the attempt to blow up his car and the situation at Solovyov’s office, insisting she wasn’t involved in his murder. Chagin tends to believe her and offers help, but demands full disclosure about her and Solovyov’s criminal dealings. He then calls Zhuk for backup. Nora identifies the murdered girls and reveals they all worked for Solovyov’s escort agency, Black Sun. She was in charge of logistics and movements, while Lentulov handled alibis. The next day, Zhuk brings Nora to Litvinov to formally repeat her testimony. On camera, she expresses uncertainty when identifying Gleb. Vlad places her in custody.