The mysterious murder of a female student causes unrest in university circles. With a close suspect, a close associate and friend, Professor Dimitris Lainis hastens to unravel the mystery.

Investigations into the murder have begun. And while the new Deputy Chief is determined to change everything, a mysterious file reaches the hands of the Director of Police Laboratories.

Continuing the search for the murdered student, the police take DNA and fingerprints from the professors and the university staff. The pressure peaks when a new corpse is discovered.

The two victims have one thing in common: a tattoo on Medusa's head. Later, after his visit to the University, Lieutenant Sklavis finds a note with the name of a girl.

Everything shows that the organization continues its activities. And while Christina is doing an interview in prison, the police visit the mother of the murdered student. Is there any new evidence of her death.

A new suitor for the position of the leader of the organization makes his appearance. Meanwhile, police officer Carra continues the investigation, while a creepy video reaches the hands of Velissaratos.

While Lainis learns about the video, journalist Stergiou risks her life again. Meanwhile, the police continue the investigations and the unexpected meeting of two members of the organization brings upset.

All the pieces of the puzzle are in place. All that is missing is the arrest of the culprits and the identification of the Reptile. A voluntary testimony will lead the police to a meeting with him, in the subversive finale.

While Athena becomes the new Head of Homicide and Dimitris mourns the loss of his beloved Tonia, a deadly explosion forces the Department to regroup and take action.

The crisis in Apostolos's relationship with Eleni escalates. At the same time, while the police interrogate those involved in the explosion, the appearance of people from the past complicates things even more.

Danae is visiting Laini, who has now returned to his teaching duties and reveals her plans in relation to the "other me" case. Athena solves the case of 18 -year -old Melina. Masatos is in the hospital after Vanorta's attack. At the same time, a second case of homicide occurs, while the police are dealing with the explosion in the funeral home.

While Tonya's father demands answers, Christina accepts a proposal from Danae. At the same time, the police investigation into the explosion and the identification of Staikos has reached an impasse.

Forensic results turn everything upside down in the explosion case, leading to yet another impasse. Faced with new information, the police implement a plan to shake things up.

An unlikely alliance is born as the police's plan fails, forcing Laini to become involved in the investigation. Meanwhile, the authorities are informed of another murder.

The police finally achieve a major breakthrough in their investigation, thanks to the help of not only Dimitris Lainis but also some unexpected allies.

Professor Dimitris Lainis puts all the pieces of the puzzle together, while the police receive an unexpected proposal that causes moral dilemmas. Everyone is held accountable for their actions and punishment meets justice. "Nemesis" is coming for everyone.