[6] The first hour of the film follows a group of young revolutionaries as they orchestrate an elaborate plan that involves the planting of bombs across the city of Paris.

It is revealed via flashback that the bombs are made of a substance called semtex, which has been provided to the young terrorists (all either teens or university students) by Greg, the only independent adult in the group.

Their plan involves the planting of bombs in cars, high-rises, and government buildings, assassinating the head of HSBC France, and setting fire to the Jeanne d'Arc.

Sarah, her boyfriend David, and Yacine each infiltrates the floor of a skyscraper to plant a bomb, aided by Fred, an accomplice who works as a security guard at the target buildings.

After detonating the bombs remotely, the young terrorists all convene to a department store situated in the heart of Paris, intending to stay there until evening of the next day so as to escape the attention of the authorities.

He encounters a homeless man whom he feels sorry for and invites into the mall for food, telling him his father owns the store and has allowed him and some friends run of the place.

In quick succession, all the young members of the team are gunned down, with their attempts to bargain or plea failing without exception, leaving a string of bodies embellishing the floors of the dark store.

The website's critical consensus reads, "Nocturama uses an unorthodox perspective and repellent protagonists to offer sobering statements about modern society -- and deliver uniquely suspenseful entertainment.

[17] Jordan Hoffman of The Guardian gave the film 3 stars out of 5, describing it as "[a] provocative French hipster-terrorism picture that is too crafty to ignore, but too obnoxious to embrace.

"[18] Pamela Pianezza of Variety stated that "Bertrand Bonello's controversial portrait of Parisian radicals planning terror attacks around the city refuses to explain the unexplainable.

"[1] David Ehrlich of IndieWire gave the film a grade of "B−", writing, "It's fine that Bonello would rather raise unsettling questions than provide unhelpful answers, but his inquiry often feels every bit as confused as his characters.

"[20] Jordan Mintzer of The Hollywood Reporter said, "if you put reality aside and try to judge the movie in a sort of vacuum, there are definitely things worth salvaging — such as Bonello's assured stylistic hand, which mixes fluid Steadicam shots with an array of tantalizing soundtrack choices, as well as an elliptical narrative that brings a handful of characters together in captivating ways, especially in the film's suspenseful first half.