In 1971, four women defy ultraconservative norms and join Mexico's first female police force—only to discover that it's a publicity stunt to distract the media from a serial killer. As the body count grows, they make a pact to bring the killer to justice.
In season two, now promoted to lieutenant, María finds herself torn between the rules she's sworn to uphold and a relentless pull toward the truth when the body of a student activist is discovered, and the Azules are pulled into an investigation that reaches back to the student massacre of 1968. Before they can make sense of what they've found, the body of a person connected to that brutal chapter of history is found, sending shock waves through the department. Someone is delivering justice straight to the police's door, and the Azules are the department's last hope of stopping the killer. As María, Valentina, Gabina and Ángeles fight battles both inside and outside the precinct, buried truths rise to the surface and they're forced to confront an uncomfortable question: in a system plagued with corruption, what is the cost of fighting for their ideals?