Movie posters are essentially their own form of art. Over the decades of the movie industry, designers have perfected the many techniques needed to create a compelling film poster. We've seen some incredible ones over the years and some less than great variations.

RELATED: 10 Sci-Fi Masterpieces From The 90s That You've Probably Never Seen

The science fiction genre is one of the biggest in Hollywood and has allowed designers to make some truly legendary posters. They are usually the most creative pieces of art in the industry, but many of them hold secret details you might not have known. Here are 10 hidden details in sci-fi movie posters you may have missed.

STAR WARS: THE LAST JEDI

The most recent Star Wars film of the sequel trilogy certainly garnered mixed opinions among fans and critics alike. Before the movie launched everyone was confused as to who the last Jedi could be. They felt that perhaps the poster could have contained a clue.

While it doesn't really reveal this plot element, there is another story point that's heavily foreshadowed in the poster that you may not have realized. One of the most controversial points of the film was Luke's moment of darkness by turning on Ben Solo. The poster casts both Ben and Luke in Sith colors and pits the two against one another either side of a lightsaber, much like the flashback sequence in the film.

ARRIVAL

The Amy Adams film about language and communication was one of the most innovative sci-fi films of the last decade. It was unique in the way it portrayed the relationship between humans and aliens and raised some philosophical questions we'd never really asked.

The poster gives a subtle hint as to how the humans may have originally acted towards this supposed alien invasion. On the beach which the alien craft overshadows, there seems to be a military lineup of vehicles and people. This is a secret message of the impending threat of humanity and a very peaceful species.

DISTRICT 9

The South African science fiction cult classic really resonated with many audiences. The story of a man becoming an alien prawn doesn't immediately strike one as compelling, but after watching it the project is worthy of all of its accolades.

RELATED: 10 Times 2000s Sci-Fi Movies Predicted The Future

The poster very much teases this transition, perhaps without the audience even realizing it. Front and center on the poster is a danger sign. It showcases the image of a prawn and reads 'no humans allowed.' This is a direct reference to how eventually our human protagonist will no longer identify as such.

CLOVERFIELD

Cloverfield Poster

The Cloverfield monster was heavily guarded up to the release of the film. No one really knew what to expect going into this movie and indeed the wider Cloverfield universe usually leaves its audiences guessing. The poster managed to use these same methods.

The main image of the poster is the Statue of Liberty, albeit missing its head. For those who never saw the trailer, this is actually the last shot of that original tease for the film. It links the marketing material perfectly and teases the oncoming threat.

ALIEN

The science-fiction horror film has gone down in history as one of the best films ever. It's a bonafide classic in every sense, although audiences didn't know that going into the film of course. The actual design of the alien is still one of the most terrifying creatures on screen.

The poster for the classic managed to tease this monster by including the image of a green glowing egg. This is symbolism we've always associated with aliens now. However, there's some subliminal messaging in this poster. If you look at the design, the egg actually looks like it could be on a cinema screen, with the pattern at the bottom representing a paying audience. It helped viewers visualize what the experience would be like.

INCEPTION

Christopher Nolan's posters usually contain just as many secrets as his films. He loves for the marketing material to actually accurately tease what's coming up in his next blockbuster and the film about falling into dreams is absolutely no exception to the rule.

RELATED: 5 Sci-Fi Movie Gadgets That Are Scientifically Accurate (& 5 That Aren't)

The science fiction film centers on a husband and wife that have been tragically separated due to her mental health. She finds herself in a limbo world which you can see on the poster. Hidden in the corner is the little family home that the wife has imagined for herself in the film. If you did not know the plot of the film you definitely wouldn't spot this house!

WALL-E

The PIXAR film featuring a robot that cleans up rubbish on Earth is about as science fiction a concept as the animation studio has ever produced. The futuristic world probably isn't so far off what we could genuinely experience if we're not careful.

WALL-E is always looking to the stars and his adventure eventually takes him into deep space in order to save the human race. If you look into the eyes of WALL-E on the poster you'll actually see space reflected in them, with one bright white spot standing out; possibly EVE or the human cruiser.

ADJUSTMENT BUREAU

The Matt Damon and Emily Blunt blockbuster was a surprise hit amongst general audiences and has become a little bit of a classic. While the film is great, the poster actually manages to perfectly represent the crazy concept that emerges from it.

Throughout the film, these beings with immense powers are introduced. They can travel pretty much anywhere and are defined by the hats they wear. The poster shows a few shadows of the Bureau watching, but in the bottom left of the poster another shadow can be seen much closer; this is, of course, Anthony Mackie's character who is there to help Damon.

E.T.

The plot of E.T. is quite a simple one and perfectly replicated in the poster design that was attached to the movie marketing campaign. The film itself portrays the friendship of a young boy and this amazing alien from outer space. The poster, of course, has the iconic finger touching moment that everyone associates the film with.

But the 'go home' line is also represented when looking at the sky that's been produced for the poster. The deep-space we see is lined with stars but a few bright spots stand out. This is the home that E.T. is trying to get back to, with the lights representing the spacecraft coming to collect him.

THE DARK KNIGHT RISES

Another Christopher Nolan film now and this one also demonstrates key plot details within the poster. After the success of the Joker character in the second film of the trilogy, fans couldn't wait to watch Tom Hardy's bane on the big screen.

The story somewhat copies a traditional comic book tale about Bane breaking the back of the Batman. The film carries out this massive move and then puts Bruce Wayne into a deep pit. A large part of the movies is about him trying to escape the prison. The poster, which sees us looking up at the buildings of Gotham, actually is more alike to the hole that Bruce is trapped in, constantly looking up at the prospect of escaping and saving his city.

NEXT: 10 Sci-Fi Masterpieces From The Last Decade