In Salvador de Bahía, Agent Cardona hopes Santo's mistress might reveal the narco's whereabouts. In Madrid, Inspector Millán tracks down a suspect.

As Millán and Cardona finally close in on Santo's location, they draw everyone around them — including their loved ones — into danger.

In the past, Cardona journeys to the depths of hell while working undercover in the cartel. In the present, he ends up in Millán's crosshairs.

Cardona and Bárbara try to evade police custody while Millán navigates an internal affairs investigation into his past conduct.

After being rescued in Madrid, Cardona tries to remember what happened to him and Bárbara while they were kidnapped. Millán investigates the Norwegians.

As Cardona recalls more about the terrifying rituals he endured while held hostage, Millán investigates one of Santo's men who was operating in Spain.