The action continues from [REC], with the medical officer and a SWAT team outfitted with video cameras are sent into the sealed off apartment to control the situation.

The horror film [REC] — directed by Jaume Balagueró and Paco Plaza, and released in 2007 — was an unprecedented triumph for Spanish fantasy cinema. Fifteen years later, those responsible for the creation and worldwide success of this cinematic milestone decode its keys and resurrect the myth.

Lucio is an old Soviet general emigrated to Spain after the end of the Soviet period. Natasha is a 12 years old girl, the unknown nephew of Lucio, who is abandoned by his stepfather in the door of the house of his uncle. They don't know each other, they are both lonely people, they don't like each other... but now, the old Soviet general and the strange little girl must live together. This new situation will ask for great sacrifices to the girl and the General, they will have to look inside to find the best of themselves in the worst of their lives.

A television reporter and cameraman follow emergency workers into a dark apartment building and are quickly locked inside with something terrifying.