Criminal: UK is part of Netflix's international anthology franchise Criminal, which simultaneously produced unrelated sibling series set in France, Spain and Germany, each filmed in its own local language.

The entire show takes place within the confines of a police interrogation room and its adjoining viewing quarters, giving the series a deliberately claustrophobic setting.

The first series was filmed at Netflix's production hub Secuoya Studios, known as Ciudad de la Tele, in Madrid, the same location used for the French, Spanish and German versions of Criminal.

The second series moved production to Shepperton Studios in London instead of the Madrid hub used for series one.

Series one featured guest stars David Tennant, Hayley Atwell and Youssef Kerkour as suspects being interrogated.

In September 2020, Netflix announced Sophie Okonedo, Kit Harington, Sharon Horgan and Kunal Nayyar as the guest stars playing the accused in the second series.

The character Detective Inspector Paul Ottager, played by Nicholas Pinnock in series one, departed the unit offscreen and was replaced in series two by a new character, Detective Sergeant Jamie Reiss, played by Aymen Hamdouchi.

The second series earned two nominations at the 2021 British Academy Television Awards, for Best Supporting Actor (Kunal Nayyar) and Best Supporting Actress (Sophie Okonedo).