Astonishing facts about the sci-fi classic Alien

“In space, no one can hear you scream!”
Nearly 45 years ago, Sir Ridley Scott's 'Alien' burst onto cinema screens - literally!
Sigourney Weaver starred as heroine Ripley, who must battle the Xenomorph creature in order to survive.
The sci-fi horror classic spawned three sequels, two prequels, spin-off films, video games, comics and an upcoming TV series.
But how much do you know about the movie?