Chaos theory, a trendy part of science since the 1990s, holds that even if events unfold by a strictly logical sequence of cause and effect, you still can't predict their outcome with any reliability. Small changes, even ones too microscopic to measure with the best scientific instruments, can lead to bigger changes further down the road, until everything is different in a way nobody could have foreseen. The classic example is that the flapping of a butterfly's wings can lead later to a hurricane on the other side of the world. This "Butterfly Effect" is why, even with the best modern technology, weather forecasters still get things wrong as often as right. You'd have to know the exact position and velocity of every air and water molecule on Earth to have any chance of predicting the future flow patterns which will determine whether it's rainy or sunny next week. And quantum mechanics, via the Heisenberg uncertainty principle, holds that this knowledge is impossible to obtain.

If this is frustrating to meteorologists, it could be devastating to time travellers. If you had the power to go back in time and change history, could you actually ensure that your changes are for the better, or are you doomed to constantly find that everything you do with the best of intentions, to avert the tragedies of the past, only cause other calamities to happen in the present and future? That is the premise of the movie The Butterfly Effect.

Time travel, alternate histories, and attempts to change the past so that things work out differently, are not a novel topic for fiction, of course. Over a period of more than a century, a number of authors, artists, and producers have tackled the issue in a variety of media.

In print media, H. G. Wells' The Time Machine is usually regarded as the seminal work of the genre, though Wells' time traveller prefers to go to the future rather than attempting to change the past. However, Mark Twain's A Connecticut Yankee in King Arthur's Court actually predates the Wells book, and actually does feature an attempt to change history by introducing 19th-century technology to medieval Britain. 20th-century science fiction authors have produced a wealth of novels and short stories exploring the effects and parodoxes of time travel in many ways, from the tangled timeline of a man's life repeatedly intersecting with itself in Robert Heinlein's "By His Bootstraps" (and his later story, "All You Zombies", with an even knottier timeline with no clear beginning as it loops on itself) to the corps of "Eternals" manipulating Earth's history in Isaac Asimov's The End of Eternity. A whole genre (sometimes treated as part of science fiction, sometimes as mainstream literature) features stories told in alternative histories, such as where the South won the Civil War.

The comics have made use of related concepts as well. The DC and Marvel superhero universes long ago became multiverses, with alternate realities (Earth-1, Earth-2), branching futures, and time travel. Attempts to simplify the tangled mess (e.g., DC's Crisis on Infinite Earths) usually result in the structure becoming more complex instead. In some cases, characters have tried actively to change their own past; in a 1970s Marvel story (Marvel Two-In-One #50), the Fantastic Four's Ben Grimm went back in time to administer an antidote to his transformation to The Thing to his younger self (by his own time, his monstrous body was too hardened for the potion to work). He found, however, that this had no effect on his current self; the change took place only in a parallel world. The original story made it seem like Grimm had created the parallel world by going back in time and introducing a change, but later issues "retconned" (a comics-fan term for retroactive continuity) it so that he'd actually traveled to an already-existing alternate Earth whose history diverged earlier (New York was still called New Amsterdam).

The movies, of course, have taken up these concepts as well. Not just in the "sci-fi" genre, either; the classic It's A Wonderful Life featured an alternate Bedford Falls (turned Potterville) in which George's nonexistence had negative effects on the town and its inhabitants. (It took an angel, not a time machine, to let George see this parallel world, then return gratefully to the real world.) Along a similar vein, and probably inspired by it, was the alternate Hill Valley with Biff in control, seen in Back To The Future II. In Groundhog Day, Bill Murray's character experienced numerous versions of the same day, giving him plenty of chance by trial and error to get everything to come out to his satisfaction.

On the small screen, there have been numerous explorations of these themes as well. Star Trek, though it's primarily devoted to space travel, has had its characters travel in time on occasion, including the classic episode "City on the Edge of Forever" (1967), where the Enterprise crew faced the dilemma of whether to save a 20th-century social worker whom they'd befriended from a tragic accidental death they knew was coming, when they also knew that failing to let her die on schedule would set in motion a divergent history that included much more death and pain (including a Nazi victory in WWII), and in which the Enterprise itself would never exist.

Other TV shows related to time travel and changing history include The Time Tunnel, a '60s show where scientists gallivanted through history in a time machine; The Lost Saucer, a '70s Saturday-morning show with Ruth Buzzi and Jim Nabors as the pilots of an out-of-control flying saucer that zigzagged through space and time; Quantum Leap, where Sam "leaped" into people of various times within his lifetime and changed their lives for the better, often rewriting history in the process; Sliders, which had its protagonists travel "sideways" in time, to a succession of alternate Earths differing in ways both small and large; Early Edition, in which Gary received each day's newspaper one day in advance and ran around Chicago preventing the bad news he read there (and when he succeeded, the newspaper magically changed to reflect the new events, a device similarly used in the Back to the Future movies); and Tru Calling, a current Fox series whose title character is sent back to relive the current day by corpses seeking her help to keep from becoming corpses (rather weird).

Those were some of the American shows of this sort; other countries have also made their contributions to the genre. Of course, there's Doctor Who, the British series featuring a time-traveler who also can change his own appearance (a handy thing for the show's producers given that they've gone through many different actors playing the role over the show's long run). And if you get into Spanish-language TV, check out the Mexican show Aventuras en el Tiempo now airing weekend mornings on Univision, featuring some kids who find a time machine and use it in the course of a complex running plotline involving bad guys swindling one of the kids' grandmother out of her house (and I wish I knew enough Spanish to understand more than scattered bits of this plot!).

As a result of all of this, just about any approach to the subject has already been explored thoroughly by this point. In some stories, history is immutable, and any attempt to change it will either fail, or turn out to be part of history in the first place (the movie 12 Monkeys gives a good example of this view). In others, like the Back to the Future series, history is highly malleable. In some, nobody even tries to change anything; they just go back in time as scientific observers, or as tourists for whom the latest trendy vacation idea is to go back and see dinosaurs, or be in Dealey Plaza when the Kennedy motorcade arrives. Sometimes there's a corps of time cops working tirelessly to prevent any interference in the space-time continuum. But sometimes things still go wrong, as in the classic Ray Bradbury story, "A Sound of Thunder" (also adapted into a comic book story by EC Comics in the '50s), where a member of a "time safari" to the age of the dinosaurs ends up accidentally causing wide-ranging changes to the present-day world through a minor error. This mistake, incidentally, consisted of stepping on a butterfly, making this the first recorded instance of the Butterfly Effect.

I think the producers of the movie The Butterfly Effect would say that their work is distinguished from the ones that went before in that, as the title indicates, it takes into account the principles of chaos theory, which hadn't yet been formulated when most of the earlier works were created. In time-travel stories where history could be changed, the changes generally proceeded in a fairly linear manner, where with enough careful thought the protagonists could figure out what needed to be changed in order to bring about the desired effect, like reuniting Marty's parents-to-be in Back to the Future, averting disasters in the newspaper in Early Edition, and so on. Asimov's The End of Eternity raised this to a science, where the Eternals used intricate computation to determine, for instance, that the best way to achieve the desired state of a future century was to move a chemical bottle from one shelf to another in a laboratory; thus, the scientist fails to find it at the crucial point of an experiment, the experiment fails, the project is terminated for lack of results, and a future technology that would (in the judgment of the Eternals) cause too much social chaos in the decades and centuries to come is aborted before it begins.

In contrast, The Butterfly Effect is predicated on the idea that you can't just change something specific and expect everything else to come out right. A change that makes things better for one person may have ripple effects that screw things up pretty badly for lots of others.

But is this really a novel concept? As you've seen earlier in this review, past stories, novels, movies, comics, and TV shows have in fact featured attempts to change (or preserve) history that backfired or had unexpected side effects. It didn't require the formal invention of chaos theory to put that idea in the heads of authors. The above-cited Bradbury story is a good example. Lots of the other stories included various things going wrong in the course of trying to set history right, though they were generally only plot complications before the successful try was made. However, Groundhog Day took an enormous number of repetitions to "get right", and that's just regarding the events of a single day; over a span of years, chaos theory dictates a mind-boggling range of possible events, making it impossible to fully solve even given unlimited re-tries. (Even the best chess-playing computers haven't completely solved the game, as the combinatoric possibilities of the moves escalate beyond the number of atoms in the universe; the universe itself, of course, is more complicated than any chessboard).

The makers of The Butterfly Effect, then, don't have much of a claim to being entirely original in supposing that changing history is frustrating work, though they do have some basis to claim to have created one of the few works that focuses on this, rather than merely using it as a minor obstacle to be overcome on the way to a Hollywood happy ending.

I must, however, point out that The Butterfly Effect is not even the first movie to explicitly reference chaos theory; that was done long ago by Jurassic Park, which asserted that despite the best efforts to ensure that the newly-cloned dinosaurs couldn't escape or reproduce and thus threaten humanity, the chaotic nature of reality would ensure that something would eventually go wrong (as Murphy's Law has long held).

OK, now, after an introduction that went on much longer than I had planned (writing projects can be subject to the effects of chaos, too!), it's time (finally!) to get to The Butterfly Effect itself. Regardless of whether it was or wasn't a pioneer at exploring the chaotic effects of time-travel change, did it do a good job of it?

I'd say that depends on what you're looking for. If you want to know more about chaos theory, you won't learn very much from this movie; I'd suggest getting a good book (e.g., Chaos: Making a New Science, by James Gleick). If you're looking for thought-provoking exploration of the ramifications of time travel and changing history, you'll get something out of this movie, but you'd get even more out of a number of other works I've cited earlier. Thus, although the marketers of this movie have made some attempt to appeal to the science-fiction and science-fact-minded people who like such speculation (such as including essays by the likes of Harlan Ellison in the film's official Web site), it really fares better when thought of differently.

The better mindset to use in judging this movie is as a psychological thriller. In this vein, it's very good. It's got characters you care about and often harrowing events that happen to them, and you really feel for Evan (Ashton Kutcher) as he seeks to make things right for himself and his friends but finds that everything he does causes unexpected effects that make it worse for some or all of the people involved. Given this focus, only the changes to the important characters (and a few cameos by others more peripheral to their lives) are shown, though a more thorough treatment of the effects of chaos ought to show that even unrelated things, from the weather to baseball scores, would likely change as well (but would be less dramatic from a cinematic standpoint; however, it might well defeat any attempt to get rich by going back in time and placing sports bets!).

Since childhood, Evan has been subject to blackouts which cause him not to remember what happened at times, usually times when particularly traumatic things happened. Just how bad those things were he gets an inkling of when, in the present as a 21-year-old college student, he asks his childhood friends some questions about what happened (in his own efforts to figure out his past blackouts) and ends up causing great trauma in those people merely for bringing up the subject. So when he discovers that, by re-reading the journals he has kept since an early age, he can actually transport himself back into his earlier self during the blacked-out times, he soon begins an effort to fix things by stopping the bad stuff that happened then.

Kutcher, who's thus-far been known for less-than-intelligent characters (That 70s Show, Dude, Where's My Car?), does a good job here in showing that he's got a much wider range as an actor; hopefully, regardless of how this movie does, it will help in the future branching-out of his career. Amy Smart, who's less well-known (but who was in a movie I happened to see and review recently, Interstate 60), also did a good job as his childhood friend, and, in some versions of reality, later his girlfriend. She had to show great range of character just to play that one part, given the wide divergence in versions of her that came up in one reality after another.

Some of the other actors/actresses weren't as good; Melora Walters looks and sounds a little phony as Evan's mother. But on the whole, the movie works. Just don't expect a lot of intellectual discussion of the ramifications of time travel. (Instead, you got it in this review!)


Recommended: Yes

Movie Mood: Serious Movie
Viewing Method: Other
Film Completeness: Looked complete to me.
Worst Part of this Film: Nothing