The 25 best sci-fi movies that are out of this world

5. 2001: A Space Odyssey (1968) 

The movie: 2001 made a giant leap for cinema a full year before TV viewers watched Neil Armstrong take one small step for mankind. Adapting a short story by Arthur C. Clarke, Stanley Kubrick delivers one of the most iconic and influential sci-fi movies of all time, breaking down the barriers between lofty, cerebral sci-fi and more accessible mainstream fare. It feels incredibly modern today despite its age, thanks to its incredible cinematography and man vs. machine themes.  

Most iconic moment: Simians thumping away with bones.  

4. Star Wars: Episode V - The Empire Strikes Back (1980)

The movie: Alright, let's not beat about the bush. Empire is the best of the Star Wars films that finds our intrepid trio Luke, Han and Leia returning to fight the empire, while revealing some unexpected twists along the way. It sets the bar for all Star Wars films to beat with none yet to surpass it. It's not just the big moments that have a lasting impact, either. Human touches, grace notes, tiny details: Empire's attention to them keeps its expanding universe concrete.  

Most iconic moment: "Luke, I am your *SPOILER*." 

3. Alien (1979)

The movie: The very first Alien movie is a much quieter, suspense-filled affair than its sequel, but established the xenomorph as one of cinema's most iconic and terrifying creatures. Sigourney Weaver's Ripley makes for a fantastic hero as the creature sneaks aboard in the most gruesome way imaginable, and then systematically kills off the crew. As they try to formulate a plan to get rid of the damn thing they discover a traitor in their midst. Often copied, never bettered, Ridley Scott's Alien: Covenant has a lot to live up to.  

Most iconic moment: As the Nostromo crew chow down on their last supper before re-entering hypersleep, the tiny alien embryo decides to burst out of Kane's chest, splattering everyone with blood and killing its host. 

2. Terminator 2: Judgment Day (1991)

The movie: Returning for a second round, Arnold Schwarzenegger reprises the role of the Terminator with a twist; instead of hunting her down on Skynet's orders, he helps protect Sarah Connor and her son John who happens to be the leader of the future resistance against Skynet. The big bad this time arrives, as before, from the future in the shape of Robert Patrick's sinister T-1000. Unlike the T-800 he's a more advanced terminator model with the ability to shape-shift. The film's state-of-the-art CGI retooled the VFX industry and left audiences picking their jaws off the floor. Worthy of a slightly molten thumbs up.  

Most iconic moment: The two Terminators meet at last, beating the ever-loving shit out of each other in a mall, a highway and the empty LA flood system. One of cinema's best ever chase sequences. 

1. Blade Runner (1982)

The movie: It's not just a star of the sci-fi genre, Blade Runner is one of the best films of all time. Starring Harrison Ford as Deckard - a "Blade Runner" assigned to find and assassinate 'replicants' who are androids that look like real human beings. When four go rogue and commit a murder, Deckard is called out of retirement to track them down. Ridley Scott's immersive visuals, Vangelis' melancholic electro-score and the haunting performances fuse together perfectly. Once seen and heard, so many scenes just burn into your brain forever.

Most iconic moment: Rutger Hauer's epic final dialogue, that happens to be accompanied by gorgeous score and moody neon visuals.