Riot Police

Director Rodrigo Sorogoyen had long been fascinated by riot police officers, exploring the limits of the use of force in their profession and how violence affects their personal lives and personality.

Co-writer Isabel Peña wanted to explore the motivations of riot police, professionals seen as villains by the public whose 'raw material' is violence; the writing team was completed by Eduardo Villanueva.

To counterbalance the predominantly male, testosterone-driven world of riot police, the creators added a strong female lead, agent Laia Urquijo, inspired by Roberto Álamo's character in the film Que Dios nos perdone.

The creators considered explicitly naming former police commissioner José Manuel Villarejo, who inspired the character of Revilla, but ultimately did not use his real name.

Before filming, the cast frequently visited real riot police facilities, especially the Moratalaz police station in Madrid (headquarters of the 1st Police Intervention Unit), where actors learned to properly use the riot shield and put on the uniform.

One line in the series, in which officer López tells interrogators that one of his motivations for the job is feeling useful, was directly inspired by a real police officer the team met during research.

Filming began in Madrid on September 2, 2019 and continued until the end of December, with additional secondary shooting locations in Valencia, A Coruña and Barcelona; key Madrid locations included a corrala on Calle del Ventorrillo, Plaza del Callao, Plaza Nelson Mandela, the Moratalaz police premises, and the area around the Santiago Bernabéu stadium.

The action-heavy early episodes were shot handheld with wide-angle lenses, using extreme close-ups, low and high angles, and complex crowded long takes to create a hyperrealistic, frantic style, while the camera work became noticeably calmer and more distant as the series progressed to reflect the narrative's evolution.

Sound designer Aitor Berenguer avoided pre-recorded sound libraries and instead frequently recorded with ambisonic microphones capturing a full 360-degree sound field to create an immersive, original soundscape.

Editor Alberto del Campo, a Goya Award winner for El reino, led the editing team and used jump cuts—removing frames from continuous takes to create subtle jolts—especially in the nervous-paced early episodes, while the final episodes were edited with a much calmer rhythm.

The series' full first season was pre-screened out of competition at the 68th San Sebastián International Film Festival on September 25, 2020 (some sources cite July 30 as the announcement date), ahead of its official October 16, 2020 premiere on Movistar+.

The release was originally planned for 2021, but after the positive response to the first teaser trailer released on June 23, 2020, Movistar+ decided to move the premiere up to autumn 2020.