In Aliens, Ellen Ripley has spent 57 years in hypersleep when she is rescued.
Ripley is recovered from deep space after drifting aboard the shuttle from the Nostromo, the spacecraft featured in Alien. Because her escape shuttle is lost and she is discovered much later, Ripley has experienced only a short subjective passage of time while 57 years have elapsed for everyone else.
This time gap drives much of the film’s emotional conflict. Ripley has lost contact with her daughter, Amanda, who grows old while Ripley remains biologically unchanged. The revelation also explains why Ripley is treated as an outsider when she returns to Earth and why the destruction of the Nostromo is difficult for the authorities to accept.
The number is sometimes misremembered as 57 months or 57 years from the events of the first film. Aliens was released in 1986 and directed by James Cameron.