Science fiction offers up so many realms to explore. So many ideas. And one of the most probing and prevalent themes, usually always rich with creativity and concern, is time travel. It's a topic we can only theorize about but it's one that has ushered in some of the best sci-fi movies of all time. Ones that expand the boundaries of imagination and, often, chase us down some very cool rabbit holes.

Whether it's the story of a killer cyborg sent back in time to wipe out the future leader of a rebellion, the tale of some poor soul forced to relive the same day over and over in a time loop, or the fable of an investigator playing with time in order to solve a mystery, this particular sci-fi terrain is always fruitful. Here are the top 15 time travel films ever!

15. Palm Springs (2020)

Where to Watch: Hulu

We kick things off with a joyous, playful "time loop" flick from 2020 starring Andy Samberg and Cristin Milioti. Palm Springs features the headlining duo as strangers who attend a wedding out in the California desert and get stuck in a day they can't escape. It's a funky and fresh spin on the format featuring two characters who run the gamut of emotions and experiences involved with being able to live forever, but never being able to move forward in time. J. K. Simmons co-stars.

Check out IGN's review of Palm Springs.

14. Predestination (2014)

Where to Watch: Roku Channel (w/ ads), or rentable on most platforms

Ethan Hawke joins Succession’s Sarah Snook and Preacher's Noah Taylor in this mind-bending thriller movie from The Spierig Brothers (Daybreakers, Jigsaw. It's about a temporal agent (Hawke) who embarks on a final time-traveling assignment to prevent an elusive criminal from launching an attack that kills thousands of people. Predestination is a twisty, turny timecop treat that keeps you guessing until the very end.

Check out IGN's review of Predestination.

13. Looper (2012)

Where to Watch: Hulu, Peacock, Fubo, or rentable on most platforms

Rian Johnson's Looper stars Joseph Gordon-Levitt and Bruce Willis as the same character from different times. As the young Joe, Gordon-Levitt is a mob assassin who kills victims that get sent back in time for him to dispose of while Willis' Joe is old Joe, who, fulfilling a "Looper" contract, is supposed to be sent back and killed by his younger self. But old Joe, upon his arrival in the past, has other things in mind – namely stopping the future from being destroyed by an entity known only as The Rainmaker. Looper is a thrilling, fascinating ride. Emily Blunt, Jeff Daniels, and Paul Dano also star.

Check out IGN's review of Looper.

12. Happy Death Day (2017)

Where to Watch: Rentable on most platforms

Happy Death Day takes the "time loop" concept and wickedly infuses into slasher-horror as Jessica Rothe's Tree finds herself being killed over and over again by the same masked maniac. Once realizing she only has a few "deaths" left in her, she takes matters into her own hands and tries to figure out who's behind the mask. Happy Death Day is bleak and hilarious…and also happens to have a sequel, Happy Death Day 2U, that plunges wildly into sci-fi!

Check out IGN's review of Happy Death Day.

11. The Time Machine (1960)

Where to Watch: Rentable on most platforms

The classic 1960 film adaptation of H. G. Wells' landmark 1865 novella tells the time-honored tale of a Victorian-era inventor, here actually named H. George Wells (and played by Rod Taylor), who uses a machine of his own design to travel to the far-off future, discovering that humanity is now become two new species – the enlightened Eloi and the monstrous, underground-dwelling Morlocks. The Time Machine is a dazzling, family-friendly slice of pioneering imagination.

10. Source Code (2011)

Where to Watch: Rentable on most platforms

Sleeper hit Source Code, from Moon's Duncan Jones, unspools a unique spin on "time loop," following a U.S. Army Captain, played by Jake Gyllenhaal, who's sent, over and over, into the digital recreation of a real-life train explosion, his mission being to find out who the terrorist culprit is. It's a clever, devious mystery that also stars Michelle Monaghan, Vera Farmiga, and Jeffrey Wright.

Check out IGN's review of Source Code.

9. Time After Time (1979)

Where to Watch: Rentable on most platforms

Time After Time's bonkers hook — that being Malcolm McDowell's H.G. Wells using his time machine to track a fleeing Jack the Ripper (the late David Warner) to 1979 San Fransisco — actually makes for an entertaining, oft emotional film. This playfulness with both sci-fi and real history forms a fun, irresistible yarn that has to be seen to be believed. Wrath of Khan's Nicholas Meyer directs while Mary Steenburgen co-stars.

8. The Terminator (1984)

Where to Watch: Prime Video, Fubo, Showtime, AMC+, or rentable on most platforms

This entry is a bit of a cheat since we're also lumping T2: Judgment Day into the mix. Hey, same continuing story, same director! That being said, James Cameron's gritty, great sci-fi bloodbath, The Terminator largely popularized the idea of going back in time and killing someone to change the present (along with larger, dystopian concepts of a world-ending A.I. uprising). Arnold Schwarzenegger's T-800 and Michael Biehn's frazzled future freedom fighter use our present era (okay, 1984) like a battleground in this sci-fi firestorm.

Check out our guide on how to watch the Terminator movies in order.

7. About Time (2013)

Where to Watch: Starz add-ons, or rentable on most platforms.

Domhnall Gleeson and Rachel McAdams star in this delightful time-tinkering rom-com from Love, Actually's Richard Curtis, as Gleeson plays a young man with the ability to time travel who tries to change his past over and over in order to improve his life, and also win the girl of his dreams. Bill Nighy co-stars in this beautifully sincere film featuring phenomenal chemistry and an intriguing take on hereditary time-hopping abilities that make About Time worth watching.

6. Edge of Tomorrow (2014)

Where to Watch: Rentable on most platforms

The "time loop" concept went big with alien apocalypse flick Edge of Tomorrow (confused so much with the film's tagline "Live, Die Repeat" that Blu-ray box art waaaay emphasized the latter). Mr. & Mrs. Smith's Doug Liman directs this terrific Tom Cruise vehicle, about humanity losing war against an invading alien army that always seems to be several steps ahead. Once Cruise's over-his-head army public affairs officer gets a taste of their cosmic precognitive power, he finds himself dying over and over in battle, unable to escape the day. Emily Blunt and Bill Paxton co-star in this keenly-crafted, funny alien actioner.

Check out IGN's review of Edge of Tomorrrow.

5. Bill & Ted’s Excellent Adventure (1989)

Where to Watch: Prime Video, Cinemax Go, Fubo, Roku Channel (w/ ads), Pluto TV (w/ ads), Tubi (w/ ads) or rentable on most platforms

Two teenage metalheads from San Dimas, California recklessly, and hilariously, mosh through time, collecting (okay, mostly kidnapping) famous historical figures from in order to ace a crucial test in one of the most entertaining movies from the '80s, Bill & Ted’s Excellent Adventure. Smart and dumb collide in fabulous ways in this roller-coaster of sublime idiocy. Keanu Reeves and Alex Winter embodied these dense-but-sweet wannabe rockers to a "T," fast forming an iconic comedy duo.

Check out our guide to the best Keanu Reeves movies of all time for more.

4. Primer (2004)

Where to Watch: Rentable on Amazon, Apple, and YouTube

Shoestring budget indie film, Primer, which acts as a no-frills psychological thought experiment about the accidental discovery of time travel, is one of the most cerebral takes on temporal tampering ever. It's a stimulating, challenging chronicle of two engineers who dabble in time travel, testing its limits, only to discover the awful ramifications and consequences of fourth-dimensional meddling. It's twisty, math-y, and full tilt fascinating.

Check out IGN's review of Primer.

3. Groundhog Day (1993)

Where to Watch: Prime Video, Fubo, AMC+, or rentable on most platforms.

There were certainly "time loop" stories — in film, TV, and literature — before Harold Ramis' Groundhog Day, but this early '90s hit popularized the concept to the degree of being considered the "Grandaddy" of the subgenre. Mercilessly funny and surprisingly endearing, Groundghog Day pushed the format in new directions. All of this is accentuated by Bill Murray's exceptional performance as a shallow TV weatherman, Phil Connors, who gets stuck in a repeating February 2nd nightmare with no true explanation (other than perhaps the universe forcing him to become a better human). Andie MacDowell, Chris Elliott, and Scooter the Groundhog co-star.

2. 12 Monkeys (1995)

Where to Watch: Cinemax Go, or rentable on most platforms

Director Terry Gilliam's insane, lavish visuals stuck mainstream pay dirt with the inventive, star-studded 12 Monkeys (which also became a pretty great TV series 20 years later, by the way). Bruce Willis and Brad Pitt (who received an Oscar nomination) headlined this warped, serpentine tale of a future prisoner, from a wasteland world all but wiped out by a virus, sent back in time to track the plague's origins. "Science ain't an exact science" Willis' Cole is told as he clumsily, and harshly, arrives in both the right and wrong times, piecing together the puzzle, thinking the disease may have begun as the brainchild of a mental patient (Pitt) from a wealthy family. 12 Monkeys is freaky, funky, and full of surprises.

1. Back to the Future

Where to Watch: Fubo, AMC+, or rentable on most platforms

Robert Zemeckis' Back to the Future is not only considered one of the best front-to-back movies of all time but it laid the groundwork for time travel in a way that's influenced just about every sci-fi property since. And yes, we're cheating here again, like we did with Terminator, and also including the film's two sequels in this entry too (same story, same director!).

All the ingredients came together in all the right ways for this pivotal pop-culture milestone, tracking young Marty McFly's adventures through time as he tries to set things right for himself and his family (lest he and his siblings wind up erased or his own future kids wind up delinquents). Michael J. Fox and Christopher Lloyd create a time-hopping team for the ages (inspiring the gruesome guffaws of Rick & Morty) as Marty and local disgraced inventor (every town's got one, right?) Doc Brown. Back to the Future is the apex of witty, exciting sci-fi.

Matt Fowler is a writer for IGN, a member of the Television Critics Association, and co-host of We Enjoy Wrestling. Follow him on Twitter at @TheMattFowler and Facebook at Facebook.com/MattBFowler.

Source: IGN.com The 15 Best Time Travel Movies of All…Time