On the offchance you've not seen it I'd like to introduce you to an Italian sci-fi film from 1965 called Planet of the Vampires. The story starts with a pair of spaceships having their flight interrupted by what appears to be a distress beacon coming from an uninhabited planet.
They have a duty to investigate and upon landing their ship is somewhat damaged. They head out to investigate.
After traversing the surface of the planet is spacesuits, they come across an ancient derelict ship. As they explore the ancient spacewreck, they find the long-dead remains of the original inhabitants.
Everything seems okay except of course it isn't. They head back to the ship and everything appears normal. Until it all kicks off when it turns out that one of them's got an ALIEN INSIDE HIM. Holy shit. I bet you didn't see that one coming. Guess what happens next. The crew get picked off one by one.
Is any of this sounding familiar? Because it seems like it should perhaps sound a tad familiar.
The interesting thing about this film is that both Ridley Scott and Dan O'Bannon have said on record that neither of them had seen this film. There are other things that happen in this flick ahat aren't in Alien - There are some pretty science-fiction leather outfits and the aliens turn out to be vampires that inhabit the bodies of the dead but even so there are a lot of parallels that can't really be ignored. Saying that, I'm still glad they made Alien, wherever the "inspiration" came from.