For a writer, it's an easy way to raise the stakes -- these characters suddenly have a whole new, deeper connection you didn't even know about.

Why It Ruins Stories:

This twist tends to come up more often in a series (either TV or movie franchises), and usually it's something thrown in at the last minute (honestly, would Lucas have played up the sexual tension between Luke and Leia so much if he had known from the start that they were brother and sister? For his benefit, let's assume not). And worse, it's usually something they come back to repeatedly.

For TV writers, for example, it's become a go-to twist to drop in at the end of an episode. And in shows that are built on twists, this becomes an issue when they've pulled this one out of the bag every six episodes and by the fourth season everybody is related. We're not exaggerating, by the way -- just look at Lost. Claire and Jack turn out to be half-siblings. Daniel Faraday is also half-siblings with Penny. That creepy Horace guy turns out to be creepy Ethan's dad. The only two Asian characters introduced after the first season turn out to be father and son.

ABC Studios
Thankfully they dropped their planned "they're brothers and brothers" reveal.

In fact, one of the biggest shocks of the series comes when John Locke discovers that a man who he thought was his dad was just trying to scam him out of a kidney -- they had so many surprise relatives in this universe that the twists came from the fact that two characters weren't related. Heroes fell into this pattern, too -- Hayden Panettiere's character is Nathan Petrelli's daughter, then Meredith Gordon's daughter, then Flint's niece (and if you don't know who any of these people are because you stopped watching after the first season, that's a good sign).

Universal Television
The last season involved an evil super-carnival ... seriously.

It's bad storytelling for the same reason the Star Wars prequels were bad (well, one of the reasons): Each new connection makes the universe of the show or movie smaller. Finding out that Darth Vader built C-3PO makes it seem like everything in that vast universe revolves around a few families and friends. It's the same in any story where it's abused -- characters who meet in a cool chance encounter turn out to be long-lost brothers or some s**t, because this rich fictional landscape is actually made up of just one very unlucky family.

Sometimes it's the entire story that turns out to be a charade, such as in Shutter Island, where the audience spends the entire film thinking Leo DiCaprio is a cop who has come to an insane asylum to solve a missing-persons case, only to find out at the end that everything that occurred -- the fights, the conversations with witnesses, the clues -- were part of an orchestrated plot by the hospital staff in order to cure him (did we mention that Leo is a patient, and not a cop at all?).

Paramount Pictures
"Medical degree? What's that?"

We would refer to Shutter Island as the world's most convoluted psychological intervention, but that title still belongs to The Game, a film in which Michael Douglas is chased, shot at, nearly drowned, and stranded, only to find out in a shocking twist that it was all part of a "game" orchestrated by his brother to cure his depression.

Universal Studios
Which makes him almost as much of a dick as the real Sean Penn.

But then there is the scaled-back and somewhat less stupid version of this that plays out in half of the blockbuster action movies these days. In The Dark Knight, The Avengers, and Skyfall, the heroes go to great lengths to finally capture the villain, only to find out that everything up to that point -- including the chase, the capture, and every impromptu decision made by the protagonists -- was all part of a carefully orchestrated plan.

Why It Ruins Stories:

Generally you can identify a good twist by how it holds up when you watch the movie again. Does it still make sense the second time around, full of little hints and foreshadowing you didn't catch the first time? Or does it make the whole thing seem kind of ridiculous and tacked on when you realize that any one of a thousand variables could have thwarted the whole thing? ("So the whole plan would have been ruined if the train had been running five minutes late?!?")

Warner Bros.
He's really putting a lot of faith in his ability to get a signal in a dude's small intestine.

This is the problem with universally hated twists like "It was a dream all along!" Once you know that, the whole thing seems pointless in retrospect -- even remembering the story is pointless, since you're remembering something that didn't happen. Well, to some degree, "Your entire reality was actually a carefully orchestrated charade!" is another version of that -- it often renders everything that came before it moot.

Like in Matchstick Men, in which professional confidence man Nicolas Cage is forced to reunite with his long-lost daughter. He's caught between his immoral criminal lifestyle and the desire to be a good role model for his little girl. Eventually, he learns how to be a dad -- that's the point of the character and the story. But then (TWIST!) at the last minute he finds out she's not his daughter, but another con artist. Oh, and his best friend is in on it. And his psychiatrist. Together, they faked Cage's entire life and took us through a whole dramatic arc, just to get at his bank account details.

Warner Bros.
"s**t, I hope that Nigerian prince hasn't wired me his funds yet."

But there's also the fact that unless it's amazingly well written, it stretches the limits of what we're capable of believing. The complexity of these cons requires its architects to program the entire world down to the smallest detail, including factors the bad guy had no control over. What if one of the Gotham cops had just shot the Joker instead of arresting him? What if the Avengers didn't have the Hulk on board the flying aircraft carrier, and instead had him out on some mission? In Shutter Island, Leo's character is mentally ill -- by definition, that should have made it impossible to predict his every move (and adjust their charade accordingly), right?

Paramount Pictures
"OK, slight change of plans, as he's decided to take a break to masturbate in the woods and talk to some squirrels."

Again, it's great while you're watching it -- but usually it's when you're thinking about it later that you start to realize the writers weren't really playing fair. And then it's too late to get a refund.

This happens repeatedly in the Harry Potter franchise: In the first film, we're distracted by Snape's assholery, so we don't think to pin crimes on the least plausible (and actual) perpetrator, the sheepish and feeble Professor Quirrell.

Electronic Arts
Depicted in the video game as an anthropomorphic purple dildo.

Then it happens again in Goblet of Fire, when the good-hearted tough guy and Harry Potter protector Mad-Eye Moody turns out to be an imposter who managed to keep up the ruse for almost a year (including fooling people who had known the guy he was impersonating for decades).

Why It Ruins Stories:

This twist becomes a problem when it undoes all of the character development that came before, and thus invalidates the amount of time we spent with that person. Bruce Wayne's entire character arc in DKR is about overcoming his fear and rising to Bane's challenge ... only to find out Bane was never the problem.

Warner Bros.
But punches were always the solution.

And sometimes the effort to throw us off the scent is downright cartoonish. In The Da Vinci Code, we meet Leigh Teabing, the charming, generally harmless Ian McKellen. He's got a gentle British accent, for chrissakes! But two hours later, he's the one pulling all the strings on the psychotic villains. It's fun for a momentary thrill, but that's also two hours of character development we just flushed down the toilet. Everything the film did to endear us to the character was only to set up the cheap twist.

Columbia Pictures
"And that burning when you pee? That was me, too."

But TV can be an even worse offender, especially when (once again) it becomes clear that the writers made it up on the fly. In Veronica Mars (the series with such a devoted cult following that its fans donated $5.7 million to keep it going), the perpetually sheepish Cassidy Casablancas spent two seasons as a shy, victimized high schooler before a sudden twist revealed him to have been the perpetrator of every bad thing that had happened up to that point. Suddenly he was a rapist and a psychopath who ran a school bus off the road and blew up a plane in midair. That's two seasons -- 44 hours -- of character development completely discarded, all in service to one shocking reveal.

The problem with this is that we feel like we wasted our time, because it doesn't change what we know about the character -- instead it tells us a character never existed and introduces a new villain played by the same actor.

In Source Code, Jake Gyllenhaal gets time machined back to the past in order to figure out who blew up a passenger train earlier that morning. In the mandatory scene where his handlers explain how time travel works in this particular universe, they make it clear that what they're doing isn't really sending him back in time, but allowing him to inhabit the memories of a dude who died in the explosion -- it's really just a recording he can interact with.

Through the course of what is essentially a really morbid version of Groundhog Day, Gyllenhaal falls in love with the girlfriend of the dead man that he's wearing as a skin suit. So of course he wants to save her life, despite it being repeatedly made clear to him that it's literally impossible to change anything in the real world from his sightseeing tour of the past. Gyllenhaal's professional opinion to the contrary is "You're wrong," and then he proves it by finally saving everyone on the train by trying really, really hard.

Summit Entertainment
His trying really, really hard for butt stuff later that night would prove less successful.

That identical plot plays out in the Denzel Washington film Deja Vu (the title would be cruelly ironic if it hadn't beaten Source Code to the theaters by a few years). This time it's a ferry boat explosion, and Washington is sent back four days into the past in a way that (again) only lets him observe, once again for the purpose of catching the terrorist. And (again!) despite his superior's warnings that the technology doesn't allow them to change the past in any way, he saves the boat and gets the girl.

Why It Ruins Stories:

These are sci-fi movies, and while other genres can get away with being a little vague with the rules of the universe (how do Smurfs breed, anyway?), science fiction is all about establishing rules and playing by them. In The Matrix, there is a specific reason within the rules of that universe that Neo is suddenly able to fly -- it's all just a computer program, and the film is about him learning to master it. That's playing by the rules.

Warner Bros.
A deleted scene had the Agents calling him a racial slur, then breaking their controllers.

But in these time-travel films, they get their surprise ending by ignoring that, usually with no explanation whatsoever. The rules of their universe are just overcome by the power of ... love, or some s**t.

In Deja Vu, Denzel Washington ignores some eggheads' eggheady explanation about how he can't change the past and does it anyway, while vocally deriding the scientists' complex language as bullshit because he couldn't understand it. Same with Source Code -- Gyllenhaal just ... does it somehow. There is no explanation. Because people who are pissed off by book learnin' are totally the target audience for sci-fi. It's actually worse in the Terminator franchise, since it creates a ridiculous loop where preventing the nuclear war also prevents the guy from going back to prevent the nuclear war.

Touchstone Pictures
"Screw nuclear war, just find me a way to travel back to stop myself from doing John Q."

But logical inconsistencies aside, it also undermines what, for most of the film, you thought was the central theme: that you must come to terms with the past, because you can't change it.

Remember, the plots of these movies are always ostensibly about fixing something else. The Terminator wasn't about going back to change the past, it was about going back to stop someone else (well, a killer robot) from changing it. Gyllenhaal's and Washington's characters weren't there to stop the bombing, they were there to find out who did it. When they tack on the happy ending, what's the moral then? That we really can un-kill our loved ones if we want it badly enough? That even the unshakeable laws of the universe can yield to the awesome power of the human spirit? That no tragedy can stand up in the face of poor test screenings?

In The Sixth Sense, it turned out that Bruce Willis was dead the whole time. There's a spoiler in the previous sentence, in case you've been living on the moons of Saturn since 1998. But with this one incredible bombshell, M. Night Shyamalan did for twists what Avatar did for 3D -- every movie needs to have it now.

Hell, we were just talking about the twist ending to a Batman movie. Yes, if ever there was a franchise that lent itself to mind-bending plot twists, it's the one about a guy in a hat with bat ears who walks the street at night punching murderous clowns. The Saw movies rely wholly on the fact that there is some massive twist at the end of all of them (they even had their own "this is the twist" theme music). And of course, Shyamalan has been trying to recreate his most famous twist ending in every movie he's done since, to the point where it's become a running joke.

Disney
"The twist is that I was a hack all along."

Why It Ruins Stories:

And that is exactly the problem. Of course, a twist ending only works if it's unexpected, and it's only unexpected when most movies aren't doing it. When seemingly 80 percent of your genre has a twist ending, or when a TV series is based entirely on twists, the audience just winds up sitting back waiting for the real story to reveal itself. The movies can't foreshadow them anymore, because the moment something weird happens, the audience is like "Welp, I wonder if this scene is only taking place inside the main character's imagination? Or if the villain is actually a split-personality version of the hero?"

New Line Cinema
"Actually, the real villain is whoever greenlit this."

Speaking of which, can you imagine that Fight Club would have been as good if it had been made in the age where every other thriller had to have a split-personality twist? We've now seen it in Black Swan, The Machinist, Secret Window (despite the fact that Stephen King wrote the story it was based on back when that twist was original), Hide and Seek, The Uninvited, Perfect Stranger, Identity, The Number 23 ... and probably more we can't remember.

20th Century Fox
"I am Jack's rehashed third act."

It's almost like they've forgotten that there are all sorts of ways to surprise the viewers and keep them guessing without resorting to a cheap "Everything we told you up until now was bullshit!" trick. Hell, at this point, not yanking the rug out from under us at the end would be the most mind-blowing twist of all.

S Peter Davis is the author of the book Occam's Nightmare, a history of conspiracy theories and strange ideas, available here.

For more things we wish Hollywood would stop doing, check out 5 Movies Hollywood Needs to Stop Making Now and 5 Reasons Hollywood Needs to Stop Making Prequels.

If you're pressed for time and just looking for a quick fix, then check out 5 Weirdly Specific Scenes You See In Every Marvel Movie.

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