November 2019. A semi-submersible loaded with three tons of cocaine is seized off the Galician coast after having crossed the Atlantic. The captain, Nando, a promising young amateur boxer, travels accompanied by a Brazilian mechanic and a Colombian hitman. Three strangers locked up for almost a month in a claustrophobic handmade boat.
The theft of a truck loaded with fentanyl, orchestrated by a group of Albanians hired by the fragile alliance between Muro and the Boza-Merino tandem, puts Fernando Barreira in the difficult situation of having to be accountable to Diosdado. After numerous hardships, Nando manages to recover the truck. However, Carlitos Miranda has decided to change the rules of the game.
Fearing for his life, Muro self-inflicts injuries in prison. After escaping to the hospital, he forms an alliance with the Albanians. Miranda is pressured by Quesada, the cartel leader. It is revealed that Gema Valdés did not die and is undergoing rehabilitation after months in a coma. Nando proposes to Diosdado to increase their profits by bringing drugs via submarine, but he needs a partner:
With the help of Andrea, a young narco boat manufacturer, Nando facilitates Joao's escape. Muro and the Albanians kidnap Miranda. Gema tries to make a living as an honest citizen, while the 'marriage' of Boza-Merino begins to falter thanks to the cunning of Anxo. Muro swears to Quesada to defend the cartel's interests in Galicia.
The drugs arrive in Galicia in two semi-submersibles, leaving Dani and her new partner, Lieutenant Novoa, powerless. The Diosdado-Joao-Nando triumvirate debuts successfully. In prison, Anxo assassinates Merino on Boza's orders. Muro orders the Albanians to issue a 'search and capture' order for Barreira. Dani is suspended from her duties by Carmo due to the judge Andrade's inaction.
Carmo cold-bloodedly murders Dani after being exposed by her. Confusing him with Nando, the Albanians mistakenly kill Ionut, Cesáreo's new disciple. Unable to fulfill his commitment to Quesada, Muro immolates himself by throwing himself off a cliff. Gathered at the summit with Diosdado, Gema and Joao die in an exchange of gunfire.
