In space, no one can hear you scream! the catchy slogan that accompanies Alien sums up the unprecedented stakes of this film that will mark the history of cinema. In 1979, for the first time on screens, a mainstream feature film will mix two distinct worlds of genre cinema: science fiction and horror. Ridley Scott forever shakes up the cinematic landscape by plunging the audience into anguish with his oppressive universe and his iconic monster. The documentary looks back at the lasting impact of this masterpiece, exploring Scott’s audacity and the genesis of his unique aesthetic. In the claustrophobic corridors of the Nostromo spaceship, the heroine played by Sigourney Weaver, becomes the first strong female figure to redefine the conventions of the genre, far from the clichés of the time. By revisiting the film's key sequences, the documentary shows how Alien explores profound themes such as survival and dehumanization, while reflecting a scathing critique of the capitalist system.