Science fiction or sci-fi is one of the most popular film genres of all time. It introduces audiences to alternate worlds where anything is possible. With such a broad definition, sci-fi can literally be just about anything that the imagination can create, from monsters to aliens to non-descript entities. There are so many subcategories that fall under the sci-fi umbrella that moviegoers can watch sci-fi films non-stop and never run out of new stories and characters. When you factor in all the sequels, prequels, and parallel universes, the genre is a never-ending source of entertainment.
When skilled sci-fi writers and filmmakers tell great stories, they are able to push reality to the edge and engage audiences in something completely new. But the cool thing about the genre is that it is still entertaining even when it isn’t done well. Terrible sci-fi films with bad special effects, worn-out characters, and predictable storylines are just as fun to watch.
Old films like “The Blob” and “The Thing From Another World” are excellent introductions to the art form. Later films like “The Time Machine” and “Planet of the Apes” take viewers into an ongoing exploration of the possibilities and entice viewers to ask questions like, “What if?” Newer additions to the genre, like “Alien” and “Close Encounters of the Third Kind,” probe the depths of outer space and the possibilities of life beyond this universe.
True sci-fi fans are dedicated to the genre and are open-minded to the myriad of ways that life and other life forms can take shape, coexist, and possibly destroy one another. If you love sci-fi and want to revisit old favorites, then you must check out the list of the best classic sci-fi films. (You might also like to read about The Highest Grossing Sci-Fi Movies.)
To determine the best classic sci-fi films, 24/7 Tempo developed an index using average ratings on IMDb, an online movie database owned by Amazon, and a combination of audience scores and Tomatometer scores on Rotten Tomatoes, an online movie and TV review aggregator, as of May 2024, weighting all ratings equally. Only movies released before 1980 with at least 1,000 reviews on IMDb were considered, and documentaries were not excluded. Cast information is from IMDb.
Here is the list of the best classic sci-fi films.
50. Phantasm (1979)
Source: Courtesy of AVCO Embassy Pictures
Source: Courtesy of AVCO Embassy Pictures
- IMDb user rating: 6.7/10 (34,292 votes)
- Rotten Tomatoes audience score: 67% (24,727 votes)
- Rotten Tomatoes Tomatometer score: 74% (46 reviews)
- Cast: A. Michael Baldwin, Bill Thornbury, Reggie Bannister
49. Tarantula (1955)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 6.5/10 (9,186 votes)
- Rotten Tomatoes audience score: 51% (1,702 votes)
- Rotten Tomatoes Tomatometer score: 94% (16 reviews)
- Cast: John Agar, Mara Corday, Leo G. Carroll
48. The Andromeda Strain (1971)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.2/10 (35,245 votes)
- Rotten Tomatoes audience score: 72% (8,739 votes)
- Rotten Tomatoes Tomatometer score: 67% (39 reviews)
- Cast: James Olson, Arthur Hill, David Wayne
47. Flash Gordon Conquers the Universe (1940)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 6.8/10 (1,352 votes)
- Rotten Tomatoes audience score: 56% (432 votes)
- Rotten Tomatoes Tomatometer score: 88% (8 reviews)
- Cast: Buster Crabbe, Carol Hughes, Charles Middleton
46. Soylent Green (1973)
Source: Courtesy of Metro-Goldwyn-Mayer
Source: Courtesy of Metro-Goldwyn-Mayer
- IMDb user rating: 7.1/10 (61,132 votes)
- Rotten Tomatoes audience score: 70% (23,798 votes)
- Rotten Tomatoes Tomatometer score: 71% (38 reviews)
- Cast: Charlton Heston, Edward G. Robinson, Leigh Taylor-Young
45. The Absent Minded Professor (1961)
Source: Courtesy of Buena Vista Pictures Distribution
Source: Courtesy of Buena Vista Pictures Distribution
- IMDb user rating: 6.8/10 (7,942 votes)
- Rotten Tomatoes audience score: 62% (7,546 votes)
- Rotten Tomatoes Tomatometer score: 83% (23 reviews)
- Cast: Fred MacMurray, Nancy Olson, Keenan Wynn
44. The Nutty Professor (1963)
Source: Courtesy of Netflix
Source: Courtesy of Netflix
- IMDb user rating: 6.7/10 (17,582 votes)
- Rotten Tomatoes audience score: 67% (32,983 votes)
- Rotten Tomatoes Tomatometer score: 84% (25 reviews)
- Cast: Jerry Lewis, Stella Stevens, Del Moore
43. The Last Man on Earth (1964)
Source: Courtesy of American International Pictures
Source: Courtesy of American International Pictures
- IMDb user rating: 6.8/10 (18,637 votes)
- Rotten Tomatoes audience score: 69% (11,627 votes)
- Rotten Tomatoes Tomatometer score: 81% (26 reviews)
- Cast: Vincent Price, Franca Bettoia, Emma Danieli
42. The Devil-Doll (1936)
Source: Courtesy of Metro-Goldwyn-Mayer
Source: Courtesy of Metro-Goldwyn-Mayer
- IMDb user rating: 7.0/10 (4,268 votes)
- Rotten Tomatoes audience score: 69% (1,238 votes)
- Rotten Tomatoes Tomatometer score: 79% (19 reviews)
- Cast: Lionel Barrymore, Maureen O’Sullivan, Frank Lawton
41. On the Beach (1959)
Source: Courtesy of United Artists
Source: Courtesy of United Artists
- IMDb user rating: 7.2/10 (12,561 votes)
- Rotten Tomatoes audience score: 69% (4,373 votes)
- Rotten Tomatoes Tomatometer score: 77% (22 reviews)
- Cast: Gregory Peck, Ava Gardner, Fred Astaire
40. Godzilla: King of the Monsters! (1956)
Source: Courtesy of Embassy Pictures
Source: Courtesy of Embassy Pictures
- IMDb user rating: 6.4/10 (7,504 votes)
- Rotten Tomatoes audience score: 73% (9,421 votes)
- Rotten Tomatoes Tomatometer score: 83% (24 reviews)
- Cast: Raymond Burr, Takashi Shimura, Momoko Kôchi
39. Slaughterhouse-Five (1972)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 6.9/10 (12,696 votes)
- Rotten Tomatoes audience score: 68% (6,235 votes)
- Rotten Tomatoes Tomatometer score: 82% (17 reviews)
- Cast: Michael Sacks, Ron Leibman, Eugene Roche
38. X: The Man with the X-Ray Eyes (1963)
Source: Courtesy of American International Pictures
Source: Courtesy of American International Pictures
- IMDb user rating: 6.6/10 (6,698 votes)
- Rotten Tomatoes audience score: 66% (3,230 votes)
- Rotten Tomatoes Tomatometer score: 88% (25 reviews)
- Cast: Ray Milland, Diana Van der Vlis, Harold J. Stone
37. Robinson Crusoe on Mars (1964)
Source: Courtesy of
Source: Courtesy of Paramount Pictures
- IMDb user rating: 6.5/10 (6,454 votes)
- Rotten Tomatoes audience score: 62% (1,711 votes)
- Rotten Tomatoes Tomatometer score: 94% (17 reviews)
- Cast: Paul Mantee, Victor Lundin, Adam West
36. It Happens Every Spring (1949)
Source: Courtesy of Twentieth Century Fox
Source: Courtesy of Twentieth Century Fox
- IMDb user rating: 6.9/10 (1,633 votes)
- Rotten Tomatoes audience score: 67% (1,050 votes)
- Rotten Tomatoes Tomatometer score: 86% (7 reviews)
- Cast: Ray Milland, Jean Peters, Paul Douglas
35. Creature from the Black Lagoon (1954)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.0/10 (28,305 votes)
- Rotten Tomatoes audience score: 74% (23,666 votes)
- Rotten Tomatoes Tomatometer score: 79% (43 reviews)
- Cast: Richard Carlson, Julie Adams, Richard Denning
34. The President’s Analyst (1967)
Source: Courtesy of Paramount Pictures
Source: Courtesy of Paramount Pictures
- IMDb user rating: 6.9/10 (3,245 votes)
- Rotten Tomatoes audience score: 78% (1,137 votes)
- Rotten Tomatoes Tomatometer score: 77% (22 reviews)
- Cast: James Coburn, Godfrey Cambridge, Severn Darden
33. Westworld (1973)
Source: Courtesy of Metro-Goldwyn-Mayer
Source: Courtesy of Metro-Goldwyn-Mayer
- IMDb user rating: 7.0/10 (55,107 votes)
- Rotten Tomatoes audience score: 70% (16,182 votes)
- Rotten Tomatoes Tomatometer score: 85% (41 reviews)
- Cast: Yul Brynner, Richard Benjamin, James Brolin
32. Monkey Business (1952)
Source: Baron / Getty Images
Source: Baron / Getty Images
- IMDb user rating: 7.0/10 (13,627 votes)
- Rotten Tomatoes audience score: 67% (8,760 votes)
- Rotten Tomatoes Tomatometer score: 88% (25 reviews)
- Cast: Cary Grant, Ginger Rogers, Marilyn Monroe
31. Fantastic Voyage (1966)
Source: Courtesy of Twentieth Century Fox
Source: Courtesy of Twentieth Century Fox
- IMDb user rating: 6.8/10 (18,085 votes)
- Rotten Tomatoes audience score: 67% (6,881 votes)
- Rotten Tomatoes Tomatometer score: 91% (33 reviews)
- Cast: Stephen Boyd, Raquel Welch, Edmond O’Brien
30. THX 1138 (1971)
Source: Courtesy of Warner Bros.
Source: Courtesy of Warner Bros.
- IMDb user rating: 6.7/10 (49,969 votes)
- Rotten Tomatoes audience score: 74% (28,201 votes)
- Rotten Tomatoes Tomatometer score: 86% (63 reviews)
- Cast: Robert Duvall, Donald Pleasence, Don Pedro Colley
29. The Beast from 20,000 Fathoms (1953)
Source: Courtesy of Warner Bros.
Source: Courtesy of Warner Bros.
- IMDb user rating: 6.7/10 (7,433 votes)
- Rotten Tomatoes audience score: 68% (2,686 votes)
- Rotten Tomatoes Tomatometer score: 95% (20 reviews)
- Cast: Paul Hubschmid, Paula Raymond, Cecil Kellaway
28. Dr. Jekyll and Mr. Hyde (1920)
Source: Courtesy of Paramount Pictures
Source: Courtesy of Paramount Pictures
- IMDb user rating: 7.0/10 (5,180 votes)
- Rotten Tomatoes audience score: 68% (3,000 votes)
- Rotten Tomatoes Tomatometer score: 92% (13 reviews)
- Cast: John Barrymore, Martha Mansfield, Brandon Hurst
27. Time After Time (1979)
Source: Courtesy of Orion Pictures
Source: Courtesy of Orion Pictures
- IMDb user rating: 7.1/10 (17,624 votes)
- Rotten Tomatoes audience score: 72% (7,020 votes)
- Rotten Tomatoes Tomatometer score: 87% (31 reviews)
- Cast: Malcolm McDowell, Mary Steenburgen, David Warner
26. The War of the Worlds (1953)
Source: Courtesy of Paramount Pictures
Source: Courtesy of Paramount Pictures
- IMDb user rating: 7.1/10 (34,039 votes)
- Rotten Tomatoes audience score: 71% (65,706 votes)
- Rotten Tomatoes Tomatometer score: 88% (34 reviews)
- Cast: Gene Barry, Ann Robinson, Les Tremayne
25. The Thing from Another World (1951)
Source: Courtesy of RKO Radio Pictures
Source: Courtesy of RKO Radio Pictures
- IMDb user rating: 7.1/10 (28,449 votes)
- Rotten Tomatoes audience score: 73% (7,995 votes)
- Rotten Tomatoes Tomatometer score: 86% (37 reviews)
- Cast: Kenneth Tobey, Margaret Sheridan, James Arness
24. The Time Machine (1960)
Source: Courtesy of Metro-Goldwyn-Mayer
Source: Courtesy of Metro-Goldwyn-Mayer
- IMDb user rating: 7.6/10 (39,104 votes)
- Rotten Tomatoes audience score: 79% (19,503 votes)
- Rotten Tomatoes Tomatometer score: 76% (38 reviews)
- Cast: Rod Taylor, Alan Young, Yvette Mimieux
23. Colossus: The Forbin Project (1970)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.1/10 (8,632 votes)
- Rotten Tomatoes audience score: 76% (2,129 votes)
- Rotten Tomatoes Tomatometer score: 88% (8 reviews)
- Cast: Eric Braeden, Susan Clark, Gordon Pinsent
22. The Fly (1958)
Source: Courtesy of Twentieth Century Fox
Source: Courtesy of Twentieth Century Fox
- IMDb user rating: 7.1/10 (21,850 votes)
- Rotten Tomatoes audience score: 71% (11,169 votes)
- Rotten Tomatoes Tomatometer score: 95% (40 reviews)
- Cast: David Hedison, Patricia Owens, Vincent Price
21. Son of Frankenstein (1939)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.1/10 (9,593 votes)
- Rotten Tomatoes audience score: 71% (3,902 votes)
- Rotten Tomatoes Tomatometer score: 95% (37 reviews)
- Cast: Boris Karloff, Basil Rathbone, Bela Lugosi
20. Island of Lost Souls (1932)
Source: Courtesy of Paramount Pictures
Source: Courtesy of Paramount Pictures
- IMDb user rating: 7.4/10 (8,788 votes)
- Rotten Tomatoes audience score: 82% (2,420 votes)
- Rotten Tomatoes Tomatometer score: 88% (40 reviews)
- Cast: Kathleen Burke, Charles Laughton, Bela Lugosi
19. Them! (1954)
Source: Courtesy of
Source: Courtesy of Warner Bros.
- IMDb user rating: 7.2/10 (20,982 votes)
- Rotten Tomatoes audience score: 77% (8,735 votes)
- Rotten Tomatoes Tomatometer score: 97% (30 reviews)
- Cast: James Whitmore, Edmund Gwenn, Joan Weldon
18. Dr. Jekyll and Mr. Hyde (1931)
Source: Courtesy of Paramount Pictures
Source: Courtesy of Paramount Pictures
- IMDb user rating: 7.6/10 (13,209 votes)
- Rotten Tomatoes audience score: 80% (5,663 votes)
- Rotten Tomatoes Tomatometer score: 90% (41 reviews)
- Cast: Halliwell Hobbes, Fredric March, Miriam Hopkins
17. Invasion of the Body Snatchers (1978)
Source: Courtesy of United Artists
Source: Courtesy of United Artists
- IMDb user rating: 7.4/10 (56,317 votes)
- Rotten Tomatoes audience score: 81% (35,471 votes)
- Rotten Tomatoes Tomatometer score: 92% (61 reviews)
- Cast: Donald Sutherland, Brooke Adams, Jeff Goldblum
16. The Incredible Shrinking Man (1957)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.6/10 (17,039 votes)
- Rotten Tomatoes audience score: 82% (3,894 votes)
- Rotten Tomatoes Tomatometer score: 92% (26 reviews)
- Cast: Grant Williams, Randy Stuart, April Kent
15. Sleeper (1973)
Source: Courtsey of United Artists
Source: Courtsey of United Artists
- IMDb user rating: 7.2/10 (42,162 votes)
- Rotten Tomatoes audience score: 81% (30,618 votes)
- Rotten Tomatoes Tomatometer score: 100% (36 reviews)
- Cast: Woody Allen, Diane Keaton, John Beck
14. Seconds (1966)
Source: Courtesy of Paramount Pictures
Source: Courtesy of Paramount Pictures
- IMDb user rating: 7.7/10 (18,912 votes)
- Rotten Tomatoes audience score: 87% (4,496 votes)
- Rotten Tomatoes Tomatometer score: 89% (35 reviews)
- Cast: Rock Hudson, Frank Campanella, John Randolph
13. Mad Love (1935)
Source: Courtesy of Metro-Goldwyn-Mayer
Source: Courtesy of Metro-Goldwyn-Mayer
- IMDb user rating: 7.3/10 (4,916 votes)
- Rotten Tomatoes audience score: 81% (2,084 votes)
- Rotten Tomatoes Tomatometer score: 100% (12 reviews)
- Cast: Peter Lorre, Frances Drake, Colin Clive
12. Planet of the Apes (1968)
Source: Courtsey of Twentieth Century Fox
Source: Courtsey of Twentieth Century Fox
- IMDb user rating: 8.0/10 (172,247 votes)
- Rotten Tomatoes audience score: 87% (119,124 votes)
- Rotten Tomatoes Tomatometer score: 86% (59 reviews)
- Cast: Charlton Heston, Roddy McDowall, Kim Hunter
11. Close Encounters of the Third Kind (1977)
Source: Courtesy of Columbia Pictures
Source: Courtesy of Columbia Pictures
- IMDb user rating: 7.6/10 (192,000 votes)
- Rotten Tomatoes audience score: 85% (142,184 votes)
- Rotten Tomatoes Tomatometer score: 94% (64 reviews)
- Cast: Richard Dreyfuss, François Truffaut, Teri Garr
10. The Invisible Man (1933)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.7/10 (32,518 votes)
- Rotten Tomatoes audience score: 85% (11,208 votes)
- Rotten Tomatoes Tomatometer score: 94% (51 reviews)
- Cast: Claude Rains, Gloria Stuart, William Harrigan
9. Forbidden Planet (1956)
Source: Courtesy of Metro-Goldwyn-Mayer
Source: Courtesy of Metro-Goldwyn-Mayer (MGM)
- IMDb user rating: 7.6/10 (47,116 votes)
- Rotten Tomatoes audience score: 85% (21,506 votes)
- Rotten Tomatoes Tomatometer score: 96% (45 reviews)
- Cast: Walter Pidgeon, Anne Francis, Leslie Nielsen
8. The Day the Earth Stood Still (1951)
Source: Courtesy of Twentieth Century Fox
Source: Courtesy of Twentieth Century Fox
- IMDb user rating: 7.7/10 (79,521 votes)
- Rotten Tomatoes audience score: 87% (34,285 votes)
- Rotten Tomatoes Tomatometer score: 95% (57 reviews)
- Cast: Michael Rennie, Patricia Neal, Hugh Marlowe
7. Invasion of the Body Snatchers (1956)
Source: Courtesy of United Artists
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Source: Courtesy of United Artists
- IMDb user rating: 7.7/10 (47,052 votes)
- Rotten Tomatoes audience score: 85% (19,223 votes)
- Rotten Tomatoes Tomatometer score: 98% (57 reviews)
- Cast: Kevin McCarthy, Dana Wynter, Larry Gates
6. The Bride of Frankenstein (1935)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.8/10 (45,621 votes)
- Rotten Tomatoes audience score: 87% (24,880 votes)
- Rotten Tomatoes Tomatometer score: 98% (47 reviews)
- Cast: Boris Karloff, Elsa Lanchester, Colin Clive
5. A Clockwork Orange (1971)
Source: Courtesy of Warner Bros.
Source: Courtesy of Warner Bros.
- IMDb user rating: 8.3/10 (785,984 votes)
- Rotten Tomatoes audience score: 93% (437,137 votes)
- Rotten Tomatoes Tomatometer score: 86% (73 reviews)
- Cast: Malcolm McDowell, Patrick Magee, Michael Bates
4. King Kong (1933)
Source: Courtesy of RKO Radio Pictures
Source: Courtesy of RKO Radio Pictures
- IMDb user rating: 7.9/10 (82,510 votes)
- Rotten Tomatoes audience score: 86% (90,230 votes)
- Rotten Tomatoes Tomatometer score: 98% (66 reviews)
- Cast: Fay Wray, Robert Armstrong, Bruce Cabot
3. Frankenstein (1931)
Source: Courtesy of Universal Pictures
Source: Courtesy of Universal Pictures
- IMDb user rating: 7.8/10 (68,290 votes)
- Rotten Tomatoes audience score: 87% (5,681 votes)
- Rotten Tomatoes Tomatometer score: 100% (49 reviews)
- Cast: Colin Clive, Mae Clarke, Boris Karloff
2. 2001: A Space Odyssey (1968)
Source: Courtesy of Metro-Goldwyn-Mayer (MGM)
Source: Courtesy of Metro-Goldwyn-Mayer (MGM)
- IMDb user rating: 8.3/10 (629,868 votes)
- Rotten Tomatoes audience score: 89% (299,429 votes)
- Rotten Tomatoes Tomatometer score: 92% (113 reviews)
- Cast: Keir Dullea, Gary Lockwood, William Sylvester
1. Alien (1979)
Source: Courtesy of Twentieth Century Fox
Source: Courtesy of Twentieth Century Fox
- IMDb user rating: 8.4/10 (823,459 votes)
- Rotten Tomatoes audience score: 94% (460,436 votes)
- Rotten Tomatoes Tomatometer score: 98% (126 reviews)
- Cast: Sigourney Weaver, Tom Skerritt, John Hurt