Alien (1979)

In director Ridley Scott's atmospheric sci-fi thriller:

• the early scene of Nostromo crew member Kane (John Hurt) being attacked by the 'face-hugging' alien as he explored the alien ship - and later the attempt to surgically remove the parasitic Alien from Kane's face, spilling an acid-like substance
• the horrifying, bloody, gory sequence revealing the birth of the sharp-toothed baby alien from the bursting chest of Kane and its scurrying across the floor

Kane's Gory Death From Alien Birth

• the life-and-death struggle with the relentless Alien
• the scene of the bludgeoning of Ash (Ian Holm) revealing that he was an android/robot
• the reactivation of Ash's severed head when he warned: "You still don't understand what you're dealing with"
• the scene of crew-member Ripley's (Sigourney Weaver) question to "Mother" (the ship's computer) and its harsh answer: "Insure return of organism for analysis. All other considerations secondary. Crew expendable"
• the Alien's head-splitting murder of crew member Brett (Harry Dean Stanton) when he searched for the crew's cat named Jones
• in an air shaft of the Nostromo, Dallas with a flame-thrower was guided with the help of a tracker to try and locate the alien - when suddenly the tracker screen showed a second dot moving ominously straight toward him: (Navigator Lambert (Veronica Cartwright): "Oh God, it's moving right towards you. Move! Get out of there!"; the Alien attacked with two hands upraised when Dallas turned and shined his light onto it - the monitor screen ended its transmission with static and a very high-pitched whine

Sole Survivor	Expelling Alien From Airlock

• and the final scene on the shuttle craft when the sole remaining Ripley - ready for hibernation and stripped down to mini-bikini panties and T-shirt - realized the Alien was still onboard, and how she carefully donned a spacesuit and fought the creature to the death by expelling it out of the airlock and incinerating it in the ship's engine blast