An investigator named Younes Falahati is put in charge of the case of alcohol poisoning and the deaths of several famous doctors. At the same time, poisoned drinks at a wedding party lead to disaster...

Police raid an illicit distillery producing counterfeit alcohol. Shahab is consumed by overwhelming guilt after Reyhaneh loses her sight. The sudden return of Sheyda, Yones's first wife, complicates matters further.

Yones and his family mourn the death of Haji Rahim. A confrontational reunion between Yones and Sheyda leads to mutual threats. Lab tests on the drinks served at the wedding reveal that the poisoning was intentional.

Shams and other guests from his son's wedding are brought in for questioning, revealing new leads. While the bond between Ava and her mother Sheyda deepens, new conflicts begin to emerge.

Shams receives alarming news about the kidnapping of his grandson, Parsa. Sheyda escalates the pressure on Yones, leaving Ava torn between staying and leaving.

Fifteen years earlier, Yones takes on a case involving the pharmaceutical poisoning of several students, which traces back to Sheyda's brother, Mohsen—a discovery that drastically impacts Yones's personal life.

Yones's ongoing struggle with his past and a secret hidden by Hana puts a severe strain on their relationship. Meanwhile, Ava and her friend are detained by the police on drug possession charges.

Hana uncovers secret meetings between Hamoon and his son. Yones is offered a promotion with a one-week deadline to wrap up his pending cases. Behzad discovers a critical new lead in the child abduction investigation.