WMG / Home Alone

Marv is drunk or on drugs in the second film
  • It would explain why he seems so much dumber and goofier than in the first film.
  • Perhaps the head injuries he sustained in film one have played havoc on him?

Kevin, his family, and Harry and Marv all get killed in the second film and the final twenty minutes or so of the movie takes place in the afterlife
  • Marv dies when he gets electrocuted, Harry when he sticks his flaming head in the kerosene-filled toilet, and Kevin himself dies either in the ensuing fire or from some other mishap (such as possibly falling into one of his own traps). Kevin, Harry and Marv wind up in Purgatory where the next segment of the film takes place, and when the pigeon lady shows up to rescue Kevin from Harry and Marv, she is actually an angel sent by God from Heaven to save Kevin; the cops who arrest Harry and Marv are Satan's minions coming to take them to Hell. Kevin's mom dies when she is murdered by a random thug on the streets of New York (especially considering it was the early 90s, back when crime was still rampant in New York City), and joins Kevin in Purgatory, and the rest of Kevin's family are killed in a plane crash while transporting their bodies back to Chicago. The last scenes of the movie take place in Heaven where Kevin's family are reunited with him and the mom—note the cheery mood and how brightly lit the "hotel suite" is.

Kevin grows up to be Jigsaw
  • Kevin was quite adept at dishing out vigilante justice with a variety of gruesome traps, particularly for an 8-year-old. It takes a twisted mind to permanently brand someone with a doorknob. His neglectful parents apparently never bothered getting Kevin therapy after two felons threatened to torture and murder him, since he deliberately runs away from a second family vacation, and his traps are noticeably more brutal in New York. Imagine what a kid like that would grow up to be.
    • As a preteen, he was like Henry Evans.
    • Chris Columbus in the commentary did say that he once pitched an idea where a grown-up Kevin escapes from prison. You might be on to something.
      • So Kevin grows up, gets sent to prison for something (most likely a trap or prank gone horribly wrong), escapes during a prison riot (which he himself caused), flees the state, hides away until the heat is off, and legally has his name changed to John Kramer. It's all falling into place!

Kevin grows up to be The Collector, is more like it.
Because he does booby traps, not death traps. And the premise of The Collector is basically an R-rated Home Alone. Maybe grown up Kevin doesn't care about justice anymore; instead he's simply a sadist, and the Comedic Sociopathy has turned into Torture Porn.

More cheerfully, Kevin grows up to be a brilliant engineer/mechanic/architect/etc. Perhaps he is already a child prodigy in one or more of those fields.
Actually building those traps (rather than just thinking them up) is quite beyond the skill of most children, as Roger Ebert pointed out. Particularly the ones in the second movie.

Even less cheerfully, Kevin grows up to be the Joker.
He has already shown a disregard for the law and a preference for chaotic, convoluted plans over straightforward ones, not to mention causing much more pain than is strictly necessary to accomplish his ends. He is adept at forcing his opposition to second, or even third-guess their own decisions. Several of his traps can only realistically work if he is either a genius at reworking his plans on the fly or he has eight or nine layers of backup plan to fall back on.
  • The progression of events is likely similar to the "Jigsaw" theory above. A prank or trap goes wrong and someone is killed or seriously hurt, Kevin goes away for a long stretch, prison changes a man, and he emerges a madman with little interest in anything except causing horrific "mischief".
    • Note that the Joker has just as much contempt for other criminals as he does for law enforcement - no doubt a result of his childhood experiences with Harry and Marv.

Harry and Marv become circus performers after serving their jail sentences following the events of the two films.
After surviving everything Kevin did to them, unscathed, they realize they can make a solid living showing off how invincible they are.

Kevin is in a coma
  • For the beginning of the film, Kevin is alive. But he is nearly killed when Buzz's shelves collapse whilst he climbs them. The rest of the film is Kevin's mind playing out an idealized sequence of events to both amuse and keep him sane: The traps he sets up and the pratfalls the Wet Bandits endure are cartoon-like, which is enough to keep him from going insane from realizing the truth.
    • That doesn't explain how Kevin's father found Harry's gold tooth at the end of the first film.
      • Still in a dream. Kevin never wakes up during the film. If you really want to make it bleak, it could be a Dying Dream.

Kevin is a distant cousin of Fred Jones
  • And trap-setting is an almost hereditary talent in their family.

Old Man Marley paid for the toothbrush...
  • After the clerk gave up chasing Kevin.
    • He was there and probably recognized the neighbour kid; and he seems nice enough.

Old Man Marley and the Bird Lady are both serial killers
  • Just because they don't kill Kevin (at least, not right now), doesn't mean that they aren't serial killers...
    • Maybe Kevin is too likeable to be killed.
      • Ask Harry and Marv about that...
    • Maybe they like him whilst Harry and Marv hate him.
      • Marley and the bird lady like Kevin because he didn't smash them with paint cans and lead pipes and irons and electrocute them and blow them up.

The Wet Bandits have some sort of medical condition, or are on some sort of drugs, that prevents them from fully feeling pain.
  • It's the only explanation apart from Rule of Funny. They do show some pain, but nothing like the agony they should be feeling, especially in the second movie.

Buzz's story about Old Man Marley...
  • Wasn't just to scare Kevin. Marley probably called him (or him and his friend[s]) out for being jerks and this was malicious slander. Scaring the crap out of his brother was an added bonus.
    • Marley makes mention of this when he speaks to Kevin in the church. Words to the tune of: "There's a lot of stuff going around about me, but none of it's true."

Kevin grows up to be John McClane from Die Hard
  • I first heard this idea on Cracked.com, don't know if they invented it. Anyway, Kevin and his family eventually enter witness protection and change their names to escape the robbers, since they're determined to kill Kevin in revenge. But Kevin himself (now called John) likes crimefighting and New York so much he returns to the city as an adult to become a police officer.

John Candy's character is Satan.
Funny how he suddenly appears right about when Kevin's Mom shouts "If I have to sell my soul to The Devil Himself, I will get home!" He accepts her offer and takes her home, torturing her with a vivid depiction of Hell (ie. trapped in a small room with a polka band) all along the way.
Donald Trump was the reason why the McCallisters got a free hotel suite.
At the time the sequel was filmed, Donald (who cameoed in it as well.) was the owner of the Plaza Hotel. He met Kevin only briefly when Kevin asked where the Lobby was. In order for the Concierge to report the stolen credit card, he would have to also report to the owner of the hotel as well as the authorities, whom in turn informed Trump of the situation. When told who the boy looked like he felt bad and ordered the staff who would have initially said no to give Kevin's family the free penthouse suite.

Harry was married and killed his wife before the first film began.
Either that or he left her, or perhaps she is also a crook and is already in jail when the films take place. This is why Harry wears a wedding band in the first film.

Marv and Harry are immortal.
This would explain how they can survive so many injuries that would kill a normal man.

Kevin was a fan of Straw Dogs.

Alex in the third film is Kevin's cousin on his mom's side.
Karen is Kate's sister.

Harry and Marv used to be plumbers.
A friend of mine pointed this out when we noticed the logo on their van: "OK Plumbing and Heating". They were plumbers who worked for a lot of wealthy houses and got greedy (either because they weren't paid well or were paid too well), leading them to become burglars. Plus, it explains their calling card as "The Wet Bandits".
  • It's either that or they stole a van and got themselves someone who could plaster a phony decal on them. Of course, the idea that they were legitimate plumbers who got greedy still makes more sense.
  • It seems more plausible that they weren't paid well because if they were paid too well, then they wouldn't have needed to stoop to thievery and could've bought whatever merchandise they wanted with their own money and still have plenty leftover, especially if they started out as legitimate plumbers. Whereas if they were underpaid, then their unhappiness with their low pay seems that much more plausible a source of influence behind what drew them to committing crime.

In the Home Alone universe everyone is Made of Iron.
Harry and Marv don't seem surprised to survive what should be deadly injuries in our universe, and don't seem to consider this as a special ability only they have. This also makes Kevin seem like less of a sociopath, if he knew they wouldn't really suffer that much.
  • This is surprisingly plausible when you consider how much pizza everyone eats. (Kevin wanted—and later got—an entire large pizza for himself, and Buzz ate a whole one before Kevin even had time to reach it!) Humans in this universe likely developed denser, stronger bones and muscles as well as a minor Healing Factor, but have higher caloric intake requirements as a result. This would also explain how Marv was able to launch Harry into the air in the second film—he weighs much more than anyone else, even other humans of this universe!

Uncle Frank is the mastermind behind everything.
Explained in detail here. Considering what an asshole and a tightwad he is, it wouldn't be surprising.

Kevin is Henry from The Good Son.
After the events of the first two films it isn't that out of place to assume social services took Kevin from the Mc Callisters because of negligence. His name got changed to protect him from Harry and Marv in the event they get out of jail and look for him. So in The Good Son he lives with a new family but tragically the events of the previous films turned him into a murderous sociopath.

The Wet Bandits are Super Soldier prototypes.
They were in prison before the events of the first film, and the US government conducted hideous human experiments on them as part of a program to develop soldiers who could survive more extreme injuries. Taking a blowtorch to the head or a kerosene explosion point-black is no problem, as they were created to withstand flamethrowers and battlefield explosives. The experiments done to them were torturously painful, resulting in them having a high enough pain threshold to keep going when an ordinary human would've been rendered comatose. They keep escaping from prison because the experiment worked too well, allowing them to get away by doing things no ordinary human could survive, like crawling through fields of barbed wire or jumping from prison walls several stories high. However, they're still only common thugs with no military training, resulting in them being unable to defeat Kevin because they just rush in and rely on their Super Toughness to survive. This is also why they're prone to dumb decisions and carelessness: they know that nothing can stop them, and are too impatient and impulsive to be more cautious.
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