The most famous one of all: is the whole film actually real, or is Quaid still in the simulation? This is a case where even the creators aren't very sure; Verhoeven says it's a fantasy, Schwarzenegger says it's real.
Just how evil was Hauser originally, especially considering he was best buddies with Cohaagen, a contemptuous sociopath in every other regard? Considering that the uncover operation as Quaid with Lori posing as his wife was supposedly all his idea, were Richter's reasons for wanting his blood solely for his actions as Quaid?
Is Lori really so aggressive toward Quaid just because he made her go to Mars? Or, like her husband, does she resent Quaid/Hauser because of how she had to sleep with him as part of the deception? She certainly didn't act that way when the deception was first revealed, but may not have wanted to antagonize someone who'd just defeated her and could have killed her.
Complete Monster: In the DC Comics adaptation of this classic action flick, by Elliot S! Maggin & Tom Lyle, Chief Administrator Vilos Cohaagen lacks his film counterpart's Villainous Friendship with Carl Hauser, while still retaining all the evil. As leader of the Mars colonization efforts, Cohaagen brutally overprices the sell of oxygen to the citizens of the colonies, uncaring that many of them are slowly dying from being unable to pay Cohaagen's prices, and, upon discovering a likely way to provide infinite oxygen across the planet, Cohaagen covers it up to retain his power over the inhabitants. When rebel forces continuously try to oust his treachery, Cohaagen devises a plan with his partner Carl Hauser to mind-wipe the latter, turning him into an ideal rebel fighter, then using this new personality, Douglas Quaid, to lead Cohaagen to the rebels. Once succeeding in this, slaughtering the entire rebel group, Cohaagen attempts to revert Quaid back to Hauser, laughing all the way about asphyxiating the entirety of Venusville for fun. Cohaagen ultimately showed his lack of care for Hauser when, after Quaid escapes the attempted reversion of his mind, Cohaagen callously orders him be killed, and spends his last moments using Melina as a hostage in an attempt to murder Quaid, securing his rule over Mars once and for all.
Crosses the Line Twice: The human shield scene. A poor bystander getting caught in the line of fire and shot by Richter's men when they're trying to kill Quaid is horrible. Quaid grabbing his corpse, using it to protect himself from several more rounds of gunfire, and then throwing his now completely bloodied up body onto his pursuers on the other hand? Hilarious.
Delusion Conclusion: The film actively plays with the idea that Quaid might just be trapped in a Lotus-Eater Machine after he visited Rekall for a fictional holiday to Mars as a secret agent. Halfway through the film, he's approached by a man who tries to convince him of this idea, only for Quaid to reject his offer with a Boom, Headshot!, figuring he's working for the bad guys from his Overly Nervous Flop Sweat while Quaid was deciding on his choice, something that he probably wouldn't have displayed if he was either communicating with Quaid from outside the simulation or a new character inserted into the simulation for the sole purpose of delivering Quaid the above message. However, there are many elements which have led viewers to conclude that it was really All Just a Dream, including Melina's face and the alien artifacts being visible on the Rekall computers and "blue sky on Mars" mentioned by one of the technicians, and the representative who visits Quaid tells him that if he doesn't snap out of his delusion, "the walls of reality will come crashing down, one minute you'll be the last hope of the Martian resistance, the next you'll be Cohaagen's bosom buddy!", all of which proceed to happen. The film also gets noticeably stranger and more surreal as time goes on, which encourages the "his mind is breaking down" idea. Then there's disagreement on whether Quaid suffered a "schizoid embolism" and was lobotomized at the end, or whether his Rekall vacation worked as intended and he simply woke up at the end.
Magnificent Bastard: Carl Hauser is the best friend and business partner of Mars' governor Vilos Cohaagen and proves to be just as brilliant as he is while being much more likeable. When the pair's exploitative practices on Mars result in mutated humans revolting against them, Hauser and Cohaagen form a scheme to have Hauser infiltrate the rebels. Seducing the rebel Melina and ingratiating himself to some of the members, Hauser then has his memories wiped and replaced with those of a man named Douglas Quaid, knowing that the psychic mutants would be able to sense his deception otherwise. Hauser records a message to Quaid, making him believe that he betrayed Cohaagen to help the rebels and giving him instructions on how to meet with their leader Kuato. Following the instructions, Quaid discovers Kuato's location, allowing Cohaagen's men to wipe out the rebels and kill Kuato. Hauser then appears in another recording, thanking Quaid and earnestly apologizing since he plans to take his memories and body back, with Quaid barely being able to avoid this fate.
Memetic Mutation: Like most Schwarzenegger films, most of the memes surrounding this film come solely from the man's iconic accent and delivery style, not to mention a number of other more memorably-delivered lines by other members of the film's cast.
Cohaagen crosses it when he leaves all the people in Venusville to suffocate via cutting off their air supply.
While Richter's Butt-Monkey and Beleaguered Assistant tendencies may have earned him a little bit of audience sympathy before, his killing of Mary the three-boobed prostitute, simply for being uncooperative, ensures that we don't feel too bad for the guy when Quaid eventually offs him in a rather gruesome manner.
Narm: Every damn scene that requires Quaid to scream in distress, stretching from the first few minutes of the film all the way to the last, thanks to Arnold Schwarzenegger's infamously limited acting abilities that result in him giving some of the most cartoonishly flatangrish imaginable. The end result sounds less like he's freaking out and more like he's peeling off the world's largest bandage.
Older Than They Think: The film utilized tropes popularized by The Matrix almost a decade before it came out such as (possibly) being stuck in a virtual dream world and being offered a Red Pill to return to reality.
During Cohaagen's death scene as he struggles to breathe on Mars, the camera cuts out a half-second too late, causing the poles used to push out the character's bulging eyes being visible as his face flops to the side.
A few seconds later (and crossing over with Freeze-Frame Bonus), the camera catches one of Quaid's eyes popping out while his features return to normal, as the Mars air rushes around him and Melinda after the volcano explodes.
Arnold's glaringly misshapen "head" when he takes off his "Two Weeks" Lady helmet/mask.
Justified, since the Johnny Cab robot is a Howdy Doody parody with a deliberately phony, chipper personality, modeled and voiced by Robert Picardo.
The scenes when Quaid takes the tracker out of his nose and when he takes off his fat lady mask. In both scenes, it's pretty easy to tell that Quaid's face is an animatronic.
The characters when their eyes bulge out of their heads when getting decompressed by Mars' atmosphere, which for some either can come off as Narm or Nightmare Fuel.
Visual Effects of Awesome: The film has well-made models and prosthetics, and the only brief CGI, in the X-ray scanner, looks simple but holds up.
The movie also took home a special achievement Academy Award for visual effects, although it's not recognized as an official "competitive" Best Visual Effects Oscar due to being the only film that got enough votes to make the nominee field cut line (the last such instance this has happened).