Be it dystopian futures, distant worlds, or elaborate concepts like time travel and parallel universes, science fiction often embraces the full creative scope of cinematic possibilities to present some of the most audacious and brain-melting movies the medium has ever seen. Even with this licence, however, some sci-fi films have made a name for themselves by pushing the boundaries of what audiences can absorb in one sitting.

Ranging from visceral cosmic horrors that unfurl with transfixing yet traumatizing visual vigor to some of the most meticulously plotted and confounding movies cinema has ever seen, . However, that doesn’t mean they aren’t worth watching. In fact, if anything, because of their eccentricities and the unique viewing experiences they offer. They might not be your cup of tea, but trust me when I say you absolutely must watch them.

The directorial debut of the ever-impressionable , is a sublime low-budget thriller from 1998, rich with hard scientific intrigue and mathematical mayhem. Max Cohen () is an unemployed number theorist who grows obsessed with his theory that universal patterns in nature can be decoded by calculating the key number. As he pursues this theory, however, the paranoid mathematician finds himself being tracked by an aggressive group with uncertain intentions.

The film’s science-fiction elements remain steeped in grounded complexity, presenting of unrestrained infatuation as Cohen sacrifices his mind and his body in his quest for answers. Intense, intricate, and entirely eerie, Pi thrives as a brilliantly conceived and fiercely intelligent sci-fi thriller that serves as a testament to how far originality and an uncompromising vision can take a shoestring budget.

It has often been said that Soviet director wasn’t so much a traditional filmmaker as he was a poet with a camera. Combine this creative might with the limitless possibilities of sci-fi storytelling, and it is no surprise that the result is international cinema has ever seen. Based on ’s novel, follows a psychologist tasked with analyzing the crew of a space station orbiting the oceanic planet Solaris, who have been led to madness by the influence of the planet.

A 166-minute exploration of human psychology that weaves together memories, dreams, obsessions, and suppressed emotional impulses, Solaris holds an eerie beauty that permeates from the allure of its characters’ descent towards insanity. It is one of Tarkovsky’s defining masterpieces, an enriching highlight of international cinema, and all lovers of the genre with its philosophical punch.

Another staggering sci-fi from Darren Aronofsky, may have been blessed with a far greater budget than the aforementioned Pi, but the appetite to weave a perplexing and convoluted narrative remains. In the modern day, a scientist searches for the fountain of youth as his wife succumbs to a brain tumor. In her manuscript, a Spanish conquistador is tasked by a princess with finding the tree of life in 16th-century Spain. Additionally, centuries in the future, an intergalactic traveler nurtures the dying tree of life en route to the heart of a dying star.

The three-pronged story cuts between narratives connected through themes of love, mortality, and obsession. While it divided fans and critics alike upon release, The Fountain demands to be seen as one of the most ambitious major studio releases this century. Bolstered by terrific performances from and , it is , narrative complexity, and sci-fi splendor.

is an unnerving and mind-bending triumph of independent film that exists as the very essence of narrative complexity in science fiction and has come to be revered as . It follows two friends and software engineers as they realize they have accidentally invented a time-travel machine. As they continue to experiment with their creation, they slowly make sense of the gravitas of what they have uncovered, and discover how it can be used to detrimental effect.

This remarkable film comes courtesy of the mathematical and engineering background of , who not only wrote, directed, and starred in the film but also produced, scored, and edited it. Primer loads its snappy 77-minute runtime with plenty of scientific detail, including an abundance of brain-melting dialogue. However, even if viewers can only understand the story in the broadest of strokes, it remains with sublime skill and comes to interesting moral conclusions. Given its density and its detail, Primer is a must-watch for all self-professed sci-fi lovers.

As if Primer wasn’t perplexing enough, Shane Carruth followed it up nine years later with another maniacal masterstroke of mind-boggling sci-fi in the form of . Kris () is a young woman dosed with a peculiar larva by a reckless scientist who observes that it makes her extremely susceptible to suggestion. A year after the ordeal, Kris befriends a man who was also experimented on. All the while, the two survivors' lives become intrinsically linked to the experiences of two pigs that have also been infected with the parasitic larvae.

Bold with its technical experimentation and exuberantly thought-provoking with its abstract narrative, Upstream Color is a decadent joy of cerebral cinema that with conviction and intelligence. Additionally, the thematic might and spiritual sensitivities of the film are as overwhelming as its plotting and presentation. The result is that lingers, hauntingly, on viewers' minds long after the credits roll.

From soaring with a certain so-bad-it’s-good infamy to simply becoming a cherished cult classic of a bygone era of sci-fi cinema, is gloriously emblematic of the B-movie science-fiction horrors of the '50s and '60s, marking an essential chapter in the genre’s history on the screen. While it does stray into areas of absurdity and senselessness with its , there is an alluring effervescence in its unrestrained approach that has made it such an iconic picture.

Directed by , it transpires as aliens enact the devious “Plan 9” that resurrects the dead to eradicate humanity from the face of the Earth. and enriched by a sense of style that, while customary of its time, has sadly gone out of date, Plan 9 from Outer Space epitomizes sci-fi in all its creative might. Its eccentricities certainly won’t be to everyone’s tastes, but it is still that demands to be seen at least once by all who love the genre.

Coming from Spain, is an underrated time-travel movie that serves as a brilliantly contained and sharply plotted story of intrigue, consequences, and desperation. When Héctor () spots a woman undressing in the woods near his home, he sets out to investigate. A violent attack, however, sees him take shelter in a mysterious building where he is convinced by a scientist to participate in a time travel experiment. As events unfold, Héctor struggles to right his wrongs while preventing more atrocities from happening.

Another low-budget masterclass that proves innovation and dare is the only necessity to making a great sci-fi, Timecrimes to deliver a time-travel thriller rife with black comedy and plenty of twists. It isn’t as convoluted as some of the other films to appear on this list, but it is an essential watch for all lovers of time-travel suspense. Today, Timecrimes has become something of a cult classic off the back of its intelligence and its intensity.

A delightful dose of '80s excess that marries sci-fi extravagance with comedic absurdity and a rousing sense of adventure, is a true cult classic of eclectic magnificence. It follows Dr. Buckaroo Banzai (), an accomplished neurosurgeon, rock star, samurai, physicist, and test pilot, as he works with his band of outrageous heroes to defend Earth from a swarm of conquering inter-dimensional aliens.

While it proved to be critically divisive, with many taking the view it was overly ridiculous and unintelligible, has endured through its magnetic energy of referential humor, over-the-top heroics, and good-natured fun. It is entirely of its time and yet remains unlike anything else to have ever graced the screen. Regardless of whether viewers love it or hate it, it is as it oversteps the line of control with enrapturing glee and a self-assurance that is admirable.

A mesmerizing marriage of cosmic horror impact and visceral visual punch, is with its eerie beauty and its striking brutality. It follows the Gardner family as their secluded farm is struck by a bizarre meteorite that emits a mystique color. As the Gardners' minds are warped by the meteorite’s influence, a raging technicolor nightmare begins to unfurl.

While it marked the first feature film effort from in 25 years, the presentation flaunts an assured confidence in its explicit excess. Every mutilated sequence of graphic visual horror has its desired impact, while the allure of the meteorite permeates an unnerving and haunting beauty. Further bolstered by a typically dynamic performance and its basis on ’s gripping short story.

A mind-bending story of time-travel mystery and fractured identities, is criminally underrated as that leaves audiences in a stunned state of shock and disarray. It follows a temporal agent traveling through time in pursuit of a serial bomber fugitive who will one day carry out an attack that kills over 11,000 people. When he encounters a tormented young soul with a horrific past, he offers them a chance to go back in time and take revenge on the person who ruined their life.

With a lead cast that includes , Sarah Snook, and Noah Taylor, Predestination thrives as a convoluted story of obsession and rising stakes that takes several striking twists and turns while remaining an absorbing and diligently well-acted drama of profound human emotions. Boldly ambitious and completely unafraid of leaving audiences perplexed, it is a sci-fi sleeper hit that has all the makings of a genre cult classic and an essential watch for anyone who loves sci-fi cinema at its most stupefying and winding.

NEXT: 10 Sci-Fi Movies From the Last 10 Years Destined To Become Cult Classics