In December 2137, fifteen years after the loss of the spaceship Nostromo, Ellen Ripley's daughter, Amanda, embarks on the most dangerous journey of her life to investigate the mysterious disappearance of her mother. For many years, no trace of the missing ship could be found. One day, a representative from Weyland-Yutani tells Amanda about the Nostromo log that was found, and then offers to study the discovery together on the inhabited space station Sevastopol, where the cargo had been delivered. Upon their arrival, they discover that armed men are roaming the station, some compartments are blocked, and remnants of law enforcement have barricaded themselves in the control center. Meanwhile, an unknown life form is methodically wiping out the station's population.