Love knows no bounds, nor does it care which planet you come from, as these romances prove. So if you feel you've run out of luck here on Earth, maybe it's time to take inspiration from these couples and start looking above and beyond -- quite literally. The fascination with intergalactic relationships has been around for some time, as is evident in the many books and films focusing on the subject. Perhaps it's the attraction of forbidden love along with the allure of outer space that keeps us wanting more.

Listed here are 15 romantic couples in film and TV that didn't let anything as petty as their humanity and (insert species here)-ity prevent them from getting together. Simple flings just won't cut it (sorry, Kirk and various alien women). For the sake of clarity, to qualify as an alien on this list, the character in question must fall under the old school definition as "a being from outer space".

Here are the 15 Best Alien/Human Couples Of All Time.

15. Dick and Mary (3rd Rock from the Sun)

Cast of 3rd Rock from the Sun

When a group of curious aliens come to Earth posing as a "traditional" American family to study our behavior, things are bound to get a little crazy. Especially when one of them falls in love with an anthropology professor. Though Dr. Mary Albright (Jane Curtin) is at first disgusted with her colleague Dick Solomon's (John Lithgow) infatuation with her, she soon succumbs to their undeniable chemistry.

Over the course of six seasons on air, these two middle-aged academics became involved in an on-and-off relationship that eventually dominated the show. Watching Dick and Mary attempting to deal with their feelings for one another was both adorable and extremely awkward at times. It 's now been 15 years since the show was cancelled, and yet the fun, nonsensical romance(s) in 3rd Rock from the Sun is still something we've held onto (even if the show's true claim to fame is launching the career of Joseph Gordon-Levitt).

14. Number Four and Sarah (I Am Number Four)

A guy and a girl talking in I am Number Four

Imagine knowing with absolute certainty that you'd met "the one" at age 16. That's what it was like for Number Four, aka John Smith, when he encountered the lovely Sarah Hart. You see, Loriens don't love like the humans -- when they fall in love, it's forever. Lucky for him, she seemed pretty into him, too.

Like so many aliens before him, Four was sent to Earth from his home planet Lorien for protection. Along with eight others, he escaped the invading Mogadorians (arguably the least impressive alien species to date), who eventually managed to track him down in Paradise, Ohio. It's Four's love for Sarah, the popular cheerleader turned reclusive photographer, that makes him stop running, plant his feet in the ground, and put up a fight. Even though he goes off to find the other stranded Loriens with bad girl Six in the end, he promises to return to Sarah, and we'd like to think that he will. But with the planned sequel having been shelved for years now, don't expect to see the pair's chapter two anytime soon.

13. Celeste and Steven (My Stepmother Is An Alien)

My Stepmother is an Alien cast

Dan Aykroyd is scientist Steven Mills, who accidentally threatens the existence of a planet in another galaxy. Enter Kim Basinger, in the shape of alien hottie Celeste, who's sent to Earth to retrieve his technology and eliminate the threat. This might be the swiftest romance on this list, as the couple gets married after knowing each other for only a day.

Steven no doubt falls for Celeste's beauty, but even her quirky traits like eating cigarette stubs and smoking carrots appear to attract him. She manages to keep her identity secret until she's discovered drinking battery fluid by Steven's daughter, Jessie, played by a young scene-stealer by the name of Alyson Hannigan (even her Buffy boyfriend, Seth Green, makes an appearance as her overconfident date). Despite some cringeworthy moments, this '80s alien rom-com remains both fun and sweet, and by the end, we somehow manage to buy that Celeste's feelings for Steven are in fact true love.

12. Spock and Uhura (Star Trek, reboot series)

Spock and Uhura from the Star Trek reboot films.

One of the more controversial additions to the new Star Trek timeline, the relationship between Spock and Uhura has been subject to much interpretation and speculation. But no matter the creators' reasons for putting these two together, we are thankful they did. For once, Kirk and his swift romantic flings are put on the sidelines, and the ultra-logical Spock gets a chance at love. When we think about it, the pairing isn't that far-fetched, and it makes sense that a sensible and strong woman like Uhura should gravitate towards the intellectual Spock.

The couple's relationship starts off as one of formality and professionalism, sprinkled with a heap of subtle hints, eventually leading to the characters openly displaying their feelings for one another. The fact that there's so much history between them makes it even more fun to speculate where this couple will end up.

11. Wanderer and Ian (The Host)

Wanderer and Ian from The Host

The 2013 movie adaptation of Stephenie Meyer's The Host had a hard time amassing the same following as her Twilight series, but regardless of what you think about the movie, its central love story far surpasses that of any vampire/werewolf/human triangle drama. We all know love is complicated, but what if you fell in love with one person, but the body you're occupying already is in love with someone else? Tricky, huh?

When Wanderer (or Wanda) takes over Melanie Stryder's body (Saoirse Ronan) she also gets Melanie's feelings for her boyfriend Jared (Max Irons). But that doesn't prevent Wanda from falling for bad boy Ian (Jake Abel) as well. As if this wasn't complicated enough, Melanie is protesting rather loudly in her head. Quite a predicament. How can this end happily, you ask? Well, let's just say the team gets creative (i.e. they find another, abandoned body). A little creepy, yes -- but oh, so romantic.

10. Valerie and Mac (Earth Girls Are Easy)

Earth Girls Are Easy

It's sweet, it's colorful, and it's just plain fun. Julien Temple's Earth Girls Are Easy from 1988 was in fact inspired by a song with the same name, which becomes clear when you watch it. In this musical rom-com, a blue, furry alien (Jeff Goldblum) receives a makeover by the beautiful and naive manicurist Valerie (Geena Davis) and promptly turns into a full-blown stud. The unlikely romance between Valerie and Mac is as crazy as it is hot (Davis and Goldblum were in fact married at the time). Throw in some dancing numbers, bubblegum, and a young Jim Carrey, and you've got yourself an instant classic.

We get to follow Mac and his two fellow aliens (post-makeover) as they chase women around L.A. after having crash-landed in Valerie's pool. When the couple finally (after a day or so) ends up in bed together, Valerie is literally taken to another dimension. No wonder she then decides to leave her cheating fiance for her alien beau.

9. John Carter and Dejah Thoris (John Carter)

John Carter - Most Expensive Movies

When Civil War veteran John Carter is transported to the planet of Barsoom (more commonly known as Mars), he encounters the gorgeous warrior princess Dejah Thoris. The two work together on their quest to defeat evil and protect the planet from destruction (which appears to be a popular pastime for couples nowadays). While the gravity on Barsoom equips John with abilities not very different from those of a superhero, Dejah is equipped with brains and a knack for fighting. As director Andrew Stanton said, these two are a "match made in the cosmos" -- and this match eventually leads to marriage.

As with most alien romantic relationships, there comes a time when the decision to return to one's home planet must be made, and unfortunately, this romance is no exception. Although John chooses to stay on Barsoom, he is taken back to Earth, where he spends every waking moment trying to get back to his wife, Dejah. Which he might have, had the film not tanked so hard at the box office.

8. Megamind and Roxanne (Megamind)

Roxanne kidnapped by Megamind

A superhero movie unlike any other requires a love story that is also one of a kind. Having been sent to Earth as a baby, with a constant stream of bad luck, outsider Megamind (Will Ferrell) decides his destiny lies in becoming the baddest supervillain the world has seen. His whole life revolves around fighting his arch enemy, Metro Man (Brad Pitt), or Mr. Goody Two-Shoes, as Megamind likes to call him.

So what happens when he finally defeats his old foe? Boredom ensues, and the brainiac villain comes up with the seemingly brilliant idea to create his own hero to fight -- Titan (or Tighten, as the "hero" himself spells it). Naturally, things don't go as planned, especially once Megamind also falls for Roxanne (Tina Fey), the whip smart reporter who supposedly was also Metro Man's number one gal (can you guess which superhero/reporter pairing acted as inspiration here? Hint: we'll be getting to them in a bit). Megamind and Roxanne's history isn't exactly the best premise for a relationship, since it mostly consisted of him kidnapping her every now and then. This is made worse when he takes the form of a museum curator to woo her. But, in the end, love conquers all.

7. Thor and Jane (MCU)

Natalie Portman and Chris Hemsworth as Thor and Jane looking at each other

Whether Thor (Chris Hemsworth) is an alien, god, or a little bit of both is a debate for another time. The point is that he is from another world, and his romance with astrophysicist Jane Foster is very much an intergalactic one. Perhaps the most picture perfect couple on this list, these two have it all going for them -- divine power (him), smarts (her), and otherwordly good looks (both). It's a shame then that they can't seem to get it to work, a sad fact that most long distance relationships have come to learn. Interfering responsibilities and families coming between them doesn't make it easier either.

No matter the rumors that we've seen the last of Natalie Portman's Jane, we won't give up on these two and still picture them ruling the world together one day -- whichever world they choose.

6. Tommy and Mary Lou (The Man Who Fell To Earth)

The Man Who Fell To Earth

Some of you may argue that Tommy never actually loved Mary Lou. We beg to differ. The story of Tommy Newton's (David Bowie) time on Earth is equally moving and depressing, and it is still the most intimate portrayal of an alien to date. With the film celebrating its 40th anniversary this October, it has been restored in 4K and is playing in theaters around the UK starting this weekend (September 9), something that was apparently in the works even before Bowie's death.

The Man Who Fell To Earth is as much a work of art as it is entertainment, and it is no wonder it quickly gained cult status. Bowie portrays the vulnerable extraterrestrial beautifully, and Candy Clark gives a great performance as the simple, sweet and needy girl who becomes obsessed with him. While Tommy never openly reciprocated Mary Lou's affections, the two form an attachment, and it is made clear by the end that he cares for her a great deal. And let's not forget the infamous gun-sex scene, which remains unmatched in its bizarreness.

5. Leeloo and Korben (The Fifth Element)

Korben and Leeloo in The Fifth Element

Luc Besson's The Fifth Element sees Korben Dallas (Bruce Willis) as the luckiest (or unluckiest?) guy alive when the perfect woman lands on the roof of his taxi one day. Not able to communicate much at first, the relationship between Korben and Leeloo (Milla Jovovich) got stronger during their quest to save the world, including a trip to the futuristic version of Club Med, Fhloston Paradise. Leeloo (shortening of a name impossible to pronounce) is a supreme, perfect being created by a group of aliens as the fifth element -- the final piece needed to defeat the Great Evil.

Having technically been born in the beginning of the movie, it is perhaps not so surprising that Leeloo is both emotional and vulnerable despite her enhanced abilities. When she questions why the world should be saved, having witnessed so much horror, Korben is there to proclaim his love for her, and in so doing, saves Earth from the Great Evil. Then they make love in the revitalizing chamber, with a bunch of scientists outside.

4. Michael and Maria (Roswell)

Michael and Maria in Roswell

For a TV show that only lasted three seasons, Roswell (or Roswell High as it also has been called) quickly accumulated a dedicated fanbase. Sadly, that just wasn't enough to get it renewed. For those of you that need a refresher, the story centers around three, Tabasco loving, alien teenagers as they try to find out the truth about who they are, all set in Roswell, New Mexico (obviously).

It might have been Max and Liz that were the show's intended main couple, but it was Michael and Maria who stole our hearts. Having been brought up by a drunk and abusive foster dad, Michael is the outsider with trust and anger management issues. He has one sole mission -- returning to his planet. When he falls for the outspoken and creative Maria, it's definitely unwillingly at first. Yet their chemistry and attachment to one another soon leads to an on-and-off relationship that lasted throughout the show. And when the time finally comes for Michael to go home to Antar, he realizes that Earth is where he belongs -- because that's where Maria is. All together now: Aww.

3. Starman and Jenny (Starman)

Starman and Jane

An anthropologist-like alien comes to Earth in response to an invitation sent up into space in the form of a record, and then gets chased down by the authorities once he arrives. Jeff Bridges was nominated for both an Academy Award and Golden Globe for his performance as the friendly, but confused, alien that crash-landed on Earth. Hoping to meet his alien friends in Arizona before the earth's atmosphere kills him, he takes the form of a dead man. With the help of the man's reluctant widow, he then makes his way to Arizona, while learning a thing or two about life on Earth along the way,(like eating pie, foul words, and sex).

Eventually they fall in love, and Starman -- the kind alien that he is -- leaves the infertile Jenny with a baby before he leaves, saying it will be both part of him and her dead husband. This was Karen Allen's first movie performance since Raiders of the Lost Ark, and it is arguably one of her best. Earlier this year, it was announced that a remake is in the works, and as exciting as that may be (Michael Douglas is on board to produce again, for what that's worth), there can be only one Starman and Jenny Hayden.

2. Jake Sully and Neytiri (Avatar)

Avatar - Same Worthington and Zoe Saldana

You knew this one was coming. This is perhaps the most adorable, albeit slightly odd, coupling on this list. In particular because Jake is human and Neytiri is 10-foot tall, blue, and a cat-like humanoid. But as we have been told so many times, love is blind. Besides, Jake Sully, the mentally and physically scarred war veteran, seemed to be more comfortable in his avatar body -- basically making him more Na'vi than human. So that makes that whole mating scene a little less weird, doesn't it?

In many ways, this is a rather traditional love story. Boy meets girl, girl thinks boy is immature, and he sets out to prove himself throughout the rest of the movie. Naturally the two fall in love, along with the obligatory parental disapproval. No matter what you think of the romance itself, the couple's journey as Neytiri tries to teach Jake what it means to be Na'vi is likely one of the most visually stunning experiences in cinematic history. And it looks like we'll be spending a lot more time with these two in the very near future, as James Cameron announced in April that the first of four sequels will be out in December 2018.

1. Superman and Lois Lane (all Superman stories)

Clarks and Lois Batman V Superman

"You've got me. Who's got you?" We might be so bold as to call this the greatest alien/human romance in history. This epic love story goes back to the very beginning; when Superman was first introduced back in 1938, Lois was right there with him. The beautiful, clever and feisty reporter has since occurred on both screen and paper as the main object of our hero's affections. Their relationship has been far from easy, having been complicated by events such as earth invasions, secret identities and even Superman's death.

The storyline most frequently used when depicting these two also sets them off to quite a rocky start where Clark is infatuated with Lois, who in turn can't think of anyone other than the beefy Man of Steel. And who can blame her? A love triangle that likely frustrated the audience as much as it did Clark/Superman ensues. Nevertheless, theirs is a romance that has proven to stand the test of time -- and paved the way for the many alien/human romantic relationships that have come since.

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Did we miss your favorite human/alien pairing? Sound off in the comments.