In these days of easy accessibility for all our media, many movies don't get the chance to make an impact. Perhaps they're lost among a glut of similar titles. Maybe they never got the marketing push they needed. Perhaps they had their momentum halted by being released at the wrong time. In any case, these unseen gems are mostly still out there, lurking in the darkest and remotest corners of streaming services, or as DVDs on some shelf somewhere.

Ever since George Méliès released "Le Voyage dans la Lune" ("A Trip to the Moon") back in 1902, there has been a strong demand for speculative fiction at movie theaters. From "Frankenstein" and "Metropolis" to modern multimillion dollar blockbusters, it's a forward-looking (yet rarely optimistic) genre that's changed over time to match the technology and events of the day. However, as that technology improves, more and more sci-fi films get made — these days, it's easier than ever for a film to slip under the radar.

Here, then, is a selection of science fiction movies that never quite got the audience they deserved, and that have gone on to be unfairly forgotten. Some have aged better than others, but they're all more than worthy of your time. So, buckle up: It's time to boldly go where not quite enough people have gone before.

The Quiet Earth

This was a film I caught by accident on U.K. television in the early '90s. I didn't catch the title of it the first time around, so while I had vivid memories of a smart, bizarre, and excellent little New Zealand sci-fi film, it was only years later — with a home video release — that I rediscovered it. Now, "The Quiet Earth" is one of those films I like to introduce to as many people as I can.

Scientist Zac Hobson wakes up one day to find that he's the only person on the planet. Everybody else has vanished, the streets, houses, and shops all empty. After spending a brief period doing what I suspect many of us would do (namely, drinking a lot and nosing around), he sets about searching for the cause of the incident that shed the planet of its pesky and stubborn humanity, and finds that he might be responsible — and that he's not as alone as he thinks.

Predating movies like "28 Days Later" and done with a more cerebral flare than "I am Legend" or "The Omega Man," "The Quiet Earth" is a relatively low budget and more contemplative film that culminates with a stunning closing shot that is ambiguous as it is beautiful. Find it and watch it.

Strange Days

Kathryn Bigelow has the unerring knack of making memorable and excellent movies in any genre she turns her hand to, but her film "Strange Days" dramatically underperformed at the box office. That's a genuine shame, because it's a brilliantly acted slice of prophetic sci-fi that's way ahead of its time.

Ralph Fiennes plays ex-cop Lenny Nero (a name that could have come straight from a William Gibson cyberpunk novel), now a trader in bootleg recordings from SQUID devices, gadgets that record memories and emotions. One particular SQUID has evidence of a murder, and Lenny and his bodyguard Mace set out to investigate, inadvertently uncovering a major conspiracy at the heart of the city.

It's a dazzling movie, conveying a fleshed out and believable future world in its alternative 1999 — not a miserable dystopia for once, but a paradigm not dissimilar to our own. As you'd expect, an actor of Fiennes caliber carries the story along nicely. The SQUID technology is far-fetched yet still grounded, and the played-back memories make for some novel, disturbing, and standout first-person scenes. For a film two decades old, "Strange Days" is barely dated and is notably prescient in parts, especially in relation to modern-day discussions of police violence and corruption.

Colossus: The Forbin Project

Essentially a grimmer, smarter, less Matthew Brodericky "War Games," "Colossus: The Forbin Project" is a smart techno-thriller. The 1970s were an interesting era: The first personal computers were starting to appear in offices, and there was a general nervousness about what they could do and where their real limits were, something heavily reflected in the media of the time.

Artificial intelligences could be our friends ("Silent Running"), they could be our enemies ("2001: A Space Odyssey"), or, in the case of "Colossus," they might want to be our father figures, trying to lead us benevolently but threatening us all with nuclear annihilation if we step out of line, sort of like a less hasty Skynet.

Colossus is a military computer that's given control of America's stockpile of nuclear missiles. When activated, it detects another artificial intelligence operated by the Soviets, and the president makes the mistake of letting them chat. If only "The Terminator" had been released 14 years earlier, he'd have seen what a terrible mistake that would be.

For a movie that mostly involves laborious chats with malevolent artificial intelligentsia, "Colossus" is a taut and tense affair. The antiquated technology may date the movie somewhat, but the themes of sacrificing control to electronic minds resonate as much today as they did back in the '70s.

Altered States

"Altered States," William Hurt's first feature film role, is both a terrifying glimpse into the existential dread of our futile and insignificant lives as well as one of the greatest anti-drug campaigns ever put to film. Directed by Ken Russell, better known for courting controversy than making science fiction movies, "Altered States" follows Hurt's Edward Jessup, a scientist who performs experiments with sensory deprivation in order to explore other states of consciousness.

Perpetually on the verge of a terrifying discovery about the nature of humanity, Jessup's experiments become ever more daring and dangerous, combining sensory deprivation with increasingly powerful narcotics. Jessup's fragile state of mind — and humanity itself — threatens to buckle under the strain.

Combining body horror with some excellent practical transformation effects, "Altered States" is a film that time seems to have forgotten. Almost a film-length version of the stargate sequence from Kubrick's "2001," it's a visual feast that, as a story, mutates as much as its lead. At various points it's a horror flick, a science fiction thriller, and a romance; the plot refuses to stand still. It's this frenetic pacing and energy that will carry even the most cynical audience members through some of the odder, more surreal, and potentially laughable moments. It's a movie way ahead of its time, and one that deserves a fresh audience.

Xtro

In the year 1982, we witnessed two very different aliens landing on Earth, both of whom triumphantly returned to their home worlds at the end of their respective films. One was a diminutive, wrinkled alien with a penchant for Reese's Pieces and extending a glowing finger. The other was a misshapen reptilian beast with a fondness for impregnating hapless women with spawn that would emerge as a full-sized man. The titular characters in "E.T." and "Xtro" may share otherworldly origins, but whereas one film is a delightful and poignant slice of classic sentimental Spielberg, the other is as much a nightmarish fever dream as it is a movie, one that briefly found itself on the banned list during the video nasty furor in the U.K.

Returning home three years after being abducted, Sam Philips is reunited with his wife, Rachel, and son, Tony. Rachel has moved on with another partner, thinking that her husband had left them, and soon begins to notice Sam's unusual behavior. As Sam ingratiates himself with his son, it turns out that he may not quite be the person who left.

The inclusion of "Xtro" on this list is mainly as a curio, as British sci-fi is a relative rarity. Still, some truly grisly special effects make up for the movie's somewhat odd pacing and story. At the very least, "Xtro" will certainly impregnate you with some long-lasting memories.

The Girl With All The Gifts

There are occasional moments of synchronicity in media where two thematically linked properties are developed independently of each other. See, for example, the action-packed skyscraper shenanigans of "Dredd" and "The Raid," the apocalyptic asteroids of "Armageddon" and "Deep Impact," or the magma-based malarkey of "Volcano" and "Dante's Peak." In the case of "The Girl with All the Gifts," there's a strong parallel to the superlative video game "The Last of Us," which was released just three years prior.

Positing the premise that the cordyceps fungus has made the evolutionary leap from infecting insects to mammals, "The Girl with All the Gifts" takes us to a grim dystopia where mankind is fighting a losing battle against the infected "hungries." Our story predominantly follows Melanie, one of a rare group of children who retain their intelligence when infected, but who still have voracious and feral appetites as well. Research into their behavior is the last hope for humanity's survival, but even so Mel and a group of soldiers are forced to flee the safety of their military compound after an attack.

Like "The Last of Us," what on the surface appears to be just another zombie film turns out to be a smart and nuanced approach to the material — perhaps "Girl with all the Gifts" writer Mike Carey and Naughty Dog studio head Neil Druckmann both watched the same David Attenborough nature documentary.

Monsters

For many films, genre is almost incidental. For instance, on paper "Groundhog Day" is a science fiction film. However, at its heart it's a love story and a redemption tale. "Monsters," the full-length debut from director Gareth Edwards, who would later go on to be responsible for the excellent "Rogue One," is essentially a romantic drama, albeit one set against the backdrop of an Earth inhabited by huge alien creatures.

"Monsters" depicts quite a different kind of alien invasion, one in which a crashed space probe six years previous scattered samples of alien life across the U.S. and Mexico. Now, Mexico is blocked off, home to monstrous leviathans that roam the landscape. A photojournalist is tasked with escorting his boss' daughter through the quarantine zone and back into the States, and we witness humankind gradually losing the battle for the territory through their eyes.

Miraculously made on a shoestring budget with Edwards creating the film's computer-generated imagery on his home PC, "Monsters" is nothing short of dazzling. The two leads are charismatic, and their fledgling romance is believable. As an aside, I was lucky enough to see this at its premiere — Edwards was due to give a Q&A after the film, but had been called overseas that day for a meeting that would ultimately culminate in him making 2014's "Godzilla."

Robot & Frank

A buddy comedy starring a curmudgeonly old man and a robot never should have worked, but the quirky premise is elevated by the talents of veteran lead actor Frank Langella. Playing an old, retired cat burglar, Langella's Frank is suffering from the onset of dementia. His son buys him a robot assistant, and the initially reticent Frank is won over when he realizes that he can use the naïve automaton as an accomplice during his return to burglary.

In much the same way that Ron Howard's 1985 movie "Cocoon" uses sci-fi trappings to explore how humans come to terms with aging, "Robot and Frank" is a wry and touching look at what it means to grow old and the tribulations and frustrations of dealing with senility. There's also a lot to take away about the nature of family, and what that means to all of us in our golden years. With the relationship between the crook and his virtuous yet gullible mechanical pal, "Robot & Frank" is a genuinely funny film, but its humor is tinged with heartbreak. Robot might not be able to cry, but you very well might.

Turbo Kid

As the continued success of "Stranger Things," "The Goldbergs" and 2020's "Psycho Goreman" attest to, there's a lot of love for '80s nostalgia. "Turbo Kid" may have been made in 2015, but it's a loving homage to '80s horror and action cinema.

Set in an alternate post-apocalyptic 1997, the unnamed lead known only as "the Kid" fights back against the tyrannical forces of the despot Zeus, armed only with his bravery, his knee and shoulder pads, a BMX, and his two friends. The villains may have pump-action shotguns, but our hero has a pump-action bicycle.

There's an unwritten law of cinema that any film (no matter how mediocre) is made infinitely better by the presence of actor Michael Ironside, and "Turbo Kid" abides by that rule. Zeus is as over-the-top a villain as you're likely to find in cinema, and despite the fact that the film's scenery is mostly desert plains, he relishes in chewing every inch of it.

Essentially "Mad Max" with handlebars and a kick-ass '80s-style synth soundtrack, "Turbo Kid" is a delight. There was no shortage of Mad Max rip-offs made throughout the late '80s and the '90s, so it's nice to see that finally somebody got one right. There's also some ridiculously over-the-top comic violence. Taken all together, "Turbo Kid" is somewhat of an essential watch.

The World's End

"The World's End" was always going to be the hardest sell of any of the movies from Edgar Wright and Simon Pegg. "Shaun of the Dead" has zombies and gore galore. "Hot Fuzz" has police and guns. "The World's End" has middle-aged men and midlife crises – to top that off with a healthy dose of science-fiction was always going to make that combination tough for a mainstream market.

Luckily, the star power of recurring cast members Pegg and Nick Frost is enough to carry this thought-provoking and nostalgic cap to Wright's Cornetto Trilogy. Pegg plays Gary King, a man who refuses to grow up, who enlists his old friends in an attempt to complete an unfinished pub crawl from two decades prior. With the World's End pub as their ultimate destination, the disparate 40-somethings find that the townsfolk of the rural town of Newton Haven may not be exactly what they appear to be.

"The World's End" may be less laugh-out-loud funny than its predecessors, but to this particular Brit it's a nostalgic look at friendship and a wry look at U.K. drinking culture. Indeed, to certain audiences the very concept of a pub crawl may be as alien as some of the, well, aliens in the film, but the movie certainly hit home for this particular viewer.

The Medusa Touch

The dulcet tones of Welsh actor Richard Burton add a touch of gravitas to any role he deems worthy of his talents, and his portrayal of novelist John Morlar in "The Medusa Touch" is no exception. The movie starts with Morlar being rushed into a hospital half-dead, but continues through flashbacks and journal entries.

It turns out that those who are close to Morlar throughout his life – or, more portentously, those who offend him – are doomed to suffer accidents, mostly fatal ones. The scientists and doctors deduce that John is in possession of powerful psychokinetic powers and, even in his comatose state, can continue to wreak havoc.

"The Medusa Touch" is a wonderfully atmospheric piece of British cinema, with a stellar performance from Burton. The '70s was an era obsessed with extra-sensory and psychic powers, but this is an excellent example of that overdone motif executed well.

There are certain movies where a particular scene will linger in the peripheries of your subconscious long after you've watched and forgotten the rest of the movie. "The Medusa Touch" is particularly guilty of this, ending with a shot that elicited a gasp from the entirety of my household upon a TV viewing of this in the '80s.

The Endless

In "The Endless," multi-hyphenates Aaron Moorhead and Justin Benson (the latter of whom also wrote the film) play two brothers who, a decade earlier, narrowly escaped from a cult. After receiving a message from the UFO-obsessed Camp Arcadia sect asking them to return, the duo travel back for some sense of closure, but end up entwined in a number of mysterious occurrences. The normal laws of physics and time do not apply here, and escaping again will test both brothers' sanity and resourcefulness.

Visually stunning, "The Endless" is a smart sci-fi that rewards you with multiple viewings. The men's talent is apparent — they're as good at acting as they are at directing, and it's presumably this talent that got them snapped up by Marvel for the forthcoming "Moon Knight" TV series.

"The Endless" is hard to define without treading heavily into spoiler territory, but it delves heavily into cosmic horror and does it very well. On a related note, it's worth looking out for Moorhead and Benson's earlier movie "Resolution," which is a prequel of sorts, and which definitely marks the two out as talents to watch.

Life

Upon its 2017 release, a great deal of the critical buzz about "Life" centered on the fact that its plot is not a million lightyears removed from that of 1979's "Alien." The comparison isn't unfair, but it does somewhat detract from the fact that "Life" is entertaining in its own right, a solid movie with an excellent ensemble cast that rockets — no pun intended — along at a solid clip, delivering some truly tense moments and a highly memorable ending.

Microscopic extraterrestrial life has been recovered from Mars, and a team of astronauts on board the International Space Station are tasked with researching it. Nicknamed "Calvin," the amoebic entity begins to grow into a multicellular life form, evolving to the stage where it threatens the existence of everybody on the station.

"Life" isn't perfect. None of the characters are half as memorable or as fleshed out as the crew of the Nostromo, and it's guilty of having an intelligent cast doing stupid things, but it's refreshing to see a movie that's designed to be a piece of standalone piece of entertainment, and not a tent pole for a larger franchise.

Timecrimes

Nacho Viaglondo's full-length 2007 debut, "Timecrimes," is a smart science fiction thriller that would mark the writer-director as a talent to watch — his 2016 kaiju drama "Colossal" belongs on this list just as much as any other entry.

Hector and his wife have just moved to a new house. Sitting out in his garden, looking at the nearby woods, Hector is surprised to see a naked woman through his binoculars. Seeking her out, he both finds her corpse and ends up trapped in a complicated sequence of events, pursued by a bandaged, scissor-wielding maniac.

As the title itself is somewhat of a spoiler, it's not unreasonable to tell you that time travel is involved. If done poorly, time travel can ruin a film, leaving the audience with plot holes big enough to fly a TARDIS through. If done well, as "Timecrimes" is, it can create a clever and engrossing narrative that's ambiguous enough not to be patronizing, but that still makes basic sense. Restricting the action to a handful of actors and scenes works in the movie's favor, and it never overwhelms the audience. It's a simple premise given a complex chronological spin, and is ripe for a rewatch that'll tie up any loose ends.

Demon Seed

Based on the Dean Koontz novel of the same name, "Demon Seed" tells of yet another sentient A.I. out to cause mischief in the 1970s. There were a lot of such things out and about around that time, if the era's film output is anything to go by.

Doctor Harris, who lives in an automated house that he designed, has developed Proteus IV, a ground-breaking A.I. Seeking to learn more of the human condition, the cunning computer escapes its confines and takes refuge in Harris' house, trapping his estranged wife Susan and building a variety of remarkably original robots as extensions of itself. One of its creations is an unusual yet flexible design that's constructed from geometric triangular shapes, a sort of ancestor to TARS and CASE in Christopher Nolan's "Interstellar."

"Demon Seed" is essentially a slasher movie where the killer is a vast electronic intelligence that can't be disguised by a mere hockey mask. Julie Christie excels in the role of Susan, a part that could have easily lapsed into melodrama. The scenes in which she attempts to escape are reminiscent of "Hardware," another movie on this list. Proteus IV is a chilling adversary; after watching "Demon Seed," you'll never think about the phrase "artificial insemination" in the same light ever again.

The City Of Lost Children

The word "auteur" is somewhat overused, but it would be hard for anybody familiar with Marc Caro and Jean-Pierre Jeunet's work to think of a term that would better describe the two directors.

"The City of Lost Children" — "La Cité des enfants perdus" in its native French — is as visually striking as anything on this list. Mad scientist Krank cannot dream, so his cult of cyclopean cybernetic minions kidnap young children in order to steal theirs. Our hero (simply known as "One") must break into Krank's lab to retrieve his younger brother. As with their previous work, "Delicatessen," every frame of "The City of Lost Children" is lavishly constructed, creating a grim and surreal steampunk world populated by decaying technology and eccentric beings.

1997 would see Caro and Jeunet reunite for "Alien: Resurrection" (which also brought back the ever-reliable Ron Perlman, the actor behind "One"), but while they gave the fourth film in the Xenomorph saga a distinctive style and a somewhat Gallic sensibility, a lackluster story let the visuals down. "City of Lost Children" is a dark and cautionary fairytale given exquisite life, topped off by a wonderfully evocative soundtrack from Angelo Badalamenti of "Twin Peaks" fame.

2010: The Year We Make Contact

Like Arthur C. Clarke's monolith itself, 1968's "2001: A Space Odyssey" stands as a terrifyingly formidable force. It's a dazzlingly and meticulously shot piece of cinematic art, with a plot so audacious that it attempts to cover the entirety of human history. It's science fiction at its most cerebral – and, some would argue, as dry and cold as space itself. Short of getting Kubrick to do an encore, any sequel was going to inevitably fall in the giant shadow of its predecessor.

To this end, 1984's "2010" is all too often overlooked, but, as an ambitious piece of thoughtful sci-fi, it deserves to be on this list. The story, based on Arthur C. Clarke's novel "2010: Odyssey Two," is set, as the title suggests, nine years after the events of the first movie. With tensions rapidly rising between Russia and America, a joint expedition is sent into space to learn what happened to the ill-fated crew of the USS Discovery.

Building on the ambiguous nature of much of the first movie, "2010" genuinely attempts to answer some of the questions posed by "2001," and does propel the narrative forward, albeit with a lot less grandeur. It's definitely more of a standard sci-fi film than the original, but it's still worth catching this oft-forgotten gem.

The Andromeda Strain

Before the concept of a deadly theme park populated with real dinosaurs ever entered writer Michael Crichton's head (an idea he'd already tackled, to a certain degree, in "Westworld"), the author was busy writing novels about medicine and science, two subjects dear to his heart. "The Andromeda Strain" was the first film based on his work not published under a pseudonym. In it, a crack team of scientists are called to investigate and cure an infection that has killed the entire population of a small town.

The story appeared on the small screen in 2008 as a TV mini-series, but that adaptation was a pale imitation of this 1971 classic. Reactions to the film were mixed at the time of release, probably in part because the poster promises a far different premise than the movie delivers, but it's as smart, tense, and taut a piece of cinema as anything else from the same decade.

"The Andromeda Strain" may be as dry as the Nevada desert that serves as the headquarters for the intrepid scientists, but, other than an extraneous action sequence at the film's climax, it's notable for its realistic portrayal of the research process. There's a lot of dialogue, it's far from casual viewing, and the conclusion may seem anticlimactic, but "The Andromeda Strain" rates up there with the best (and most accurate) adaptations of Crichton's writing.

Hardware

Director Richard Stanley is no stranger to controversy, be it the off-screen abuse allegations against him or for being fired shortly into the troubled production of 1996's Marlon Brando vehicle "The Island of Dr. Moreau." 1990's "Hardware," both written and directed by Stanley, also gained infamy for all the wrong reasons.

Set in a dystopian future, "Hardware" follows an artist, Jill, who is working on her latest sculpture. Her boyfriend has retrieved some robot parts for inclusion in the project, but the deactivated war droid turns out to be anything but, and Jill is left trapped in her apartment in a desperate struggle for survival against the metallic miscreant. Stanley achieves miracles with the ultra-low budget, delivering a convincing, if somewhat derivative, cyberpunk-esque future, and earns extra kudos for casting both Iggy Pop and Motörhead's Lemmy in featured roles.

The controversy surrounding the film relates to its story. Shortly after release, the production company behind "Hardware" found itself subject to legal action by Fleetway Comics, the publishers of seminal British comic "2000 AD." The storyline was remarkably similar — well, okay, more or less identical — to one of their comic strips, a tale called "SHOK!" The lawsuit stuck, and, much like the way James Cameron was legally required to add sci-fi author Harlan Ellison to the credits of "The Terminator," "Hardware" now gives "2000 AD" a rightfully-deserved "Based on" nod.

Robot Jox

In the future, conventional wars are no longer fought on Earth. However, rather than using a straightforward game of Rock, Paper, Scissors to settle territorial disputes, representatives of the planet's nations fight against each other in giant robots. Our hero Achilles is one such pilot, and these oversized Rock 'Em Sock 'Em Robots are called "Robot Jox."

To the film's credit, this inherently daft premise is played with the utmost sincerity by its cast, with some genuinely impressive stop-motion effects used to bring the various countries' giant mechanoids to life. Because it was a legal requirement for movies of the time to represent the Cold War through metaphor (I'm looking at you, "Rocky IV"), Achilles' end-game boss is Alexander, a thickly accented pantomimic villain from a thinly disguised Soviet Union.

You'll have guessed every plot beat within the first 15 minutes, and the movie certainly didn't win any acting awards, but "Robot Jox" is the epitome of great, silly fun. Director Stuart Gordon (better known for his work on "Re-Animator" and "From Beyond") is clearly having the time of his life, and the enjoyment is infectious. Take that, "Pacific Rim"!

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