They’re supposed to be the brightest among us, using a lifetime of education and research to save the day. But not all movie scientists are created equal. They might be book-smart, but when it comes to street-smarts, they’re often woefully under prepared.

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Whether they’re unleashing an alien monstrosity on the world or just making stupid everyday decisions, scientists can often be portrayed in sci-fi movies as an “other” separate from ordinary people. When they fail in their monumental attempts to create life, avert catastrophe, or explore the unknown, it’s usually everyday people who suffer the most. Let’s take a deeper dive into the dumbest scientists you’ll ever see on the silver screen.

7 Dr. Yueh (Dune)

Dune's Dr. Yueh on Arrakis.

On the surface, Dr. Yueh seems like a pretty clever guy. He speaks multiple languages, knows all about the history and culture of Arrakis, and has taken on young Paul Atreides as a sort of pupil. But he makes one painfully obvious mistake that throws the rest of his credibility out the window.

When House Atreides’ arch-nemesis House Harkonnen kidnaps Dr. Yueh’s wife, he feels he has no choice but to betray his friends. He sells them down the river, helping the Harkonnens storm the citadel, wiping out the Atreides’ forces. And for what? In the end, Baron Vladimir Harkonnen kills Dr. Yueh anyway, as he had done to his wife long ago. Dr. Yueh would be forgiven for letting such a personal part of his life cloud his judgment, but this was one trap any clear-headed person could have seen coming a lightyear away.

6 Ray Stantz (Ghostbusters)

Ray Stantz (Dan Aykroyd) from Ghostbusters

One of the founding Ghostbusters, Dr. Ray Stantz has some of the films’ most iconic lines. Despite having his own lab at a prestigious university, Ray’s antics keep him young at heart — but this childlike innocence can sometimes lead to some pretty dumb moments.

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When the Ghostbusters buy the building that eventually becomes their headquarters, it’s Ray who takes out a third mortgage on his family home (“the interest rate alone for the first five years comes to $95,000"). And who can forget the film’s legendary showdown with the 100-foot-tall Stay-Puft Marshmallow Man? That was all down to Ray choosing the physical form for “the destructor”. While everyone else stayed quiet, Ray just let that one slip out. He's a funny guy, sure, but sometimes it's a bit baffling how Ray ever got that PhD.

5 Dr. Arthur Carrington (The Thing From Another World)

Dr. Carrington from The Thing From Another World

The Thing From Another World is your classic sort of old-school sci-fi story. An alien crashlands in the Arctic Circle, leaving a small cohort of military, scientists, and civilians to intervene. Hauling the frozen body of the alien from the flying saucer, someone’s electric blanket inadvertently melts the ice surrounding the alien, freeing him.

When Carrington realizes that the alien is basically an intelligent, bipedal plant, he decides he needs to befriend it and learn more about its kind. However, the alien isn’t so keen on friendship, and Carrington’s actions soon endanger everybody at the base — including himself. Carrington is desperate to learn, but at what cost?

4 Dr. Brackish Okun (Independence Day)

Independence Day's Dr. Brackish Okun in Area 51.

Chief scientist at Area 51, Dr. Brackish Okun’s job for many years had been to study alien tech and reverse engineer it to benefit the US military. But while working in a subterranean facility for all those years, something inside Dr. Okun’s mind must have gone a little haywire. One look at the guy lets audiences know he isn’t quite all there anymore: the long disheveled hair, the near-reverance he has for the aliens, and the relative disregard for the rest of humanity paint a picture of a classic mad scientist.

It’s no surprise then that Dr. Okun volunteers to perform an autopsy on a captured alien, only to be possessed by the alien’s telepathic powers. Killing his colleagues before slipping into a coma himself, Dr. Okun has got to be one of the dumbest smart people on the planet.

3 Herbert West (Re-Animator)

Re-Animator's Herbert West uses a green re-animation serum.

Loosely based on an H.P. Lovecraft story, Re-Animator’s cheesy, gore-filled extravaganza of death and rebirth is a classic example of science going too far. Herbert West, a medical student, makes a breakthrough by resurrecting a dead professor. His unethical experiments leave much to be desired, though, with several specimens attacking innocent people (adding to his stockpile of available cadavers to re-animate).

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By the end of the movie, West has re-animated over a dozen corpses, including three of his own professors. West seems to enjoy torturing these poor souls, but this mad scientist seems to have overlooked some basic math. There’s only one of him, and a lot of angry zombies. Let’s just say this bloody sci-fi horror has a bloodbath or two in store for Mr. West.

2 All The Scientists (Night Of The Comet)

Scientists from Night of the Comet

As the name suggests, a radioactive comet hurtles past Earth — apparently, according to the movie, the very same one that wiped out the dinosaurs. Wiping out most life on Earth, the only survivors are those who spent the night inside some sort of shielded environment.

Somewhere out in the desert, a group of scientists had foreseen this apocalyptic event and planned ahead, housing themselves in a hidden bunker. They poured untold time, energy, and money into this plan, yet they managed to somehow mess it all up. On the night of the comet’s passage, someone forgot to shut off the vents, exposing the group of scientists to the radiation. It’s not enough to kill them instantly, but it is enough that they decide to harvest the unsullied blood of the innocent in order to stave off further infection.

1 Science Officer Ash (Alien)

Alien's Science Officer Ash, a robot disguised as a human

While it’s ultimately revealed that Ash’s seemingly idiotic actions were down to his true loyalty to the Weyland-Yutani Corporation, it’s impossible to think Ash is anything but a moron the first time one watches Alien.

From the very start, he breaks the most basic rules in the book. When one of the crew arrives back at the ship with an alien attached to his face, Warrant Officer Ripley rightly orders the affected into 24-hour quarantine outside the ship. But Ash breaks that order, letting the alien onboard the Nostromo.

Ash then proceeds to let the alien run wild in his lab, all while he tries to learn more about it. By the end of the film, he knows some vague facts about its protein structure, but as Ripley points out, while the rest of the crew has been picked off one-by-one, Ash has effectively done nothing. Ash's story arc is a fascinating one -- which may not have ever existed, had director Ridley Scott opted instead to make Dune back in the 1980s.

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