The Biggest Plot Holes In Alien Movies

Movies involving aliens depict scenarios that, as far as we know, are pretty much impossible. This is what gives them their allure — but that doesn't mean we don't expect them to preserve a logically consistent internal structure. The "science" and "fiction" elements of the genre are equally essential to the execution of a compelling piece of entertainment: Audiences need their flights of fancy to be built upon a foundation that makes sense.

Alien movies, though, often tackle such ambitious ideas that a couple of plot holes here and there are inevitable. When it comes to many of these goofs, fans can either ignore them or conjure up plausible explanations that honor their love of the film. That's a feat in and of itself: Not everyone can make a movie fans want to believe in, even when it's hard. But when one of these movies falls short of its potential in an irredeemable way, eagle-eyed viewers are quick to notice. The only battles more intense than the intergalactic wars waged in these movies are those fought in sci-fi forums over their discrepancies. These are the biggest, most blatant, and most frustrating plot holes in movies about aliens.

The issue many fans take with District 9 doesn't have to do with a confounding Easter egg or an overlooked loose end, but with an overarching fact of the story. There is, simply put, little to no effort put towards involving science in the premise of the 2009 movie. It is frankly outrageous to propose that the alien "Prawns'" extraterrestrial DNA would be so compatible with that of humans that it could intermingle, much less change human anatomy shortly after exposure. Yet that's exactly what happens — our protagonist Wikus even grows a claw overnight.

The incredulity of a discerning audience mounts when we consider the long and complex history of genetic modification in our own world, and compare it with the ugly but relatively seamless course of Wikus' mutation. There is also no rhyme or reason to the human psychology Wikus retains. He just seems to keep his mind for the sake of preserving his motivation, and thus the trajectory of the plot. Why is his human brain affected considerably less than his physique? Aren't the differences between crustacean brain structures and our own just too vast to bridge? Apparently not. 

On the subject of his physique, it's a serious lapse in MNU's security for Wikus, a former-operative-turned-fugitive of the company, to still have his fingerprint security clearance on the books, allowing him access to secure areas.

The Alien franchise doesn't just struggle with under-explanation — it outright suffers from it. A particularly major plot hole is created in Alien: Covenant, which seeks to connect 2012's Prometheus to the original franchise.

The original events of Alien begin when the crew of the spaceship Nostromo intercept a distress call from the planet LV-426. There, they discover, onboard a crashed spaceship, thousands of Xenomorph face-hugger eggs. They also discover the Space Jockey, a large humanoid from whose chest an alien apparently burst, killing him long before the crew's arrival.

In the sequel, Prometheus, we learn that the Space Jockey was actually a spacesuit for the Engineers who created humanity and subsequently destroyed the population of Earth 2000 years prior, taking all but their own with them in the process. This history means that the ship must have crashed into LV-426 centuries, if not millennia before its discovery in 2122. In Covenant, however, we learn that the android David's scientific curiosity and meddling resulted in the creation of the eggs, and that this happened in the 11-year gap between Prometheus, which took place in 2093, and the events of Covenant in 2104. Based on this timeline, there should have never been eggs on the "derelict" spacecraft, and Alien should never have happened.

The invaders in Cowboys & Aliens stop by Earth on their tour of destruction, having ravaged at least one other inhabited planet that we know of. Apparently, their mission is to travel the universe in search of gold, which sort of makes them interstellar pirates. It also means they have something in common with humans, as the 2011 film takes place shortly after the end of the California Gold Rush. We don't know why they want gold, but it's likely not because they use it as currency. Gold can conduct electricity and transmit digital data, form alloys with other metals, and help shield from radiation.

Not only would it be useful to an alien race in this manner, gold is also part of the composition of many cosmic objects. In fact, gold on earth is theorized to have been brought to the planet by asteroids. But because of this, it would actually be a much greater, and arguably prohibitive, effort to harvest gold from Earth and then expend energy to propel it back into space. The aliens could just as easily have extracted gold from a more amenable source, somewhere in space. And they wouldn't have risked an epic cinematic showdown with Earth's inhabitants, either.

Crucial plot points in 10 Cloverfield Lane rest on flawed science. For one thing, the water table in Louisiana is so high that the bunker's existence is seriously unfeasible — not to mention the fact that the city is, in fact, sinking below sea level. The frequent hurricanes and almost yearly flooding of the Mississippi River exacerbate this effect, causing the water table in the delta to fluctuate wildly. If the homes of New Orleans and greater Louisiana are at significant risk of flooding when levels rise, an underground bunker — where most of the film takes place — would have a lot of trouble surviving.

Another one of the movie's scientific inaccuracies revolves around the fictional Scottish whiskey Michelle uses for a Molotov cocktail, which is often touted as evidence of the film's attention to detail. It's actually an instance of the exact opposite. When this particular attempt at creating a Chekhov's gun appears, the camera lingers for a strikingly long moment on the bottle — long enough for us to see that it is a 27-year-old scotch weighing in at 80 proof. Whiskey can be flammable when its alcohol content exceeds 50%, or 100 proof, which means she couldn't have actually used this bottle to destroy the alien spacecraft.

One of the most iconic scenes from 1982's E.T. the Extra-Terrestrial is the moment E.T. and Elliott soar through the sky on a bicycle, propelled by the alien's science-fiction abilities. We discover that he can grant the power of flight (and also bring an audience to tears, but that's another matter) simply by lifting a finger. It's a heartwarming moment when he and Elliott share their flight earlier in the film, and a triumphant one when E.T. uses this power to help the group of friends escape the authorities along with him later on.

The magic of these scenes is undeniable, but they do beg the question: If E.T. can fly, why didn't he use that power to escape earlier and save everyone a lot of hassle? Especially considering that his strength wanes the longer he remains on Earth, and that this reduces his capacity to defend himself or escape, it's surprising that he doesn't take the opportunity to use his powers when the earliest threats present themselves. Maybe his  sentimental attachment to Elliott makes him stay put a little longer –- or maybe he just lives for the drama.

It's especially disappointing when a would-be shocking twist turns out to have a major hole in it. The plot issue in this 1956 film screws with everything, starting with the title: Invasion of the Body Snatchers. The idea the film rests upon is not that alien invaders are snatching minds, but rather that they are snatching the bodies of people on Earth and replacing them with identical-looking alien impostors. The characters in the film start finding these duplicates, so we know that the aliens aren't taking over the minds of existing bodies.

This makes the twist at the end, when Becky falls asleep for a few moments and wakes up as "one of them," to the horror of love interest Miles, a lot less compelling and way more confusing. She only falls asleep for a second before awakening as a pod person. It is never specified what happens to the original bodies, but we know that a switch is required. Yet in Becky's case, for some reason, this all goes out the window. The shock factor isn't enough to distract from the nonsensical deviation from the movie's established rules.