Terminator: Salvation hits theaters today and to commemorate that we're looking at films that veer into the fourth dimension (that's time for us non-technical folk). Time travel is a story device with all kind of possibilities built right in. If I could travel back to 2005 and locate Jennifer Aniston would I be able to convince her that making The Break-Up was a really bad idea? I can dream, can't I? Anyway, here are seven of my favorite time travel movies.

Back to the Future (1985)

Between constant reruns on basic cable and just being a pretty awesome flick is there anyone in this world who hasn't seen Back to the Future? Eccentric scientist Doc Brown (Christopher Lloyd) while demonstrating his Delorean-mounted time machine sends Marty McFly (Michael J. Fox) back to the 1950s. Marty's return to 1985 must be timed to the split second to coincide with a lightning bolt that will power the Delorean's Flux Capacitor, but in the meantime Marty disrupts the event that got his parents together thus threatening his very existence. Before he can return to his own time Marty needs to put his folks back on the path to marriage, put a bully in his place and invent the skateboard all set to the music of Huey Lewis and The News. This movie is just plain fun. The following year Lea Thompson who plays Marty's mom graduated from coming on to her own son to putting the moves on a cranky water fowl in Howard the Duck.
Groundhog Day (1993)
Here's another film that proves that time travel need not be a deathly serious affair. Bill Murray stars as Phil Connors, a self-centered TV weatherman who is on assignment to Punxsutawney (take THAT, spell check!), PA to cover the annual Groundhog Day festivities. A blizzard traps Phil and his crew in town, but when he awakens the next morning he realizes that it is still Groundhog Day and he is trapped in a time loop that only he is aware of. After several times around the loop Phil tries killing himself, but not even death will release him. Eventually he develops a conscience, starts improving himself, and begins wooing his producer Rita (Andie McDowell). At times this feels like a feature length Twilight Zone episode but it doesn't seem padded. The cast, including Chris Elliot as Larry the camera operator are all great and this is probably Murray's best film.

Primer (2004)
Primer is quite simply one of the most intelligent science fiction films you're ever going to find. This ultra low budget indie (made for around $7,000) presents time travel in such a straightforward and matter of fact manner and using such convincing technical jargon that you can almost believe it's possible. Two engineers accidentally discover a means of traveling backward through time. They figure the best way to profit from their invention is to research the most profitable stocks at the end of each day then travel back to that morning and invest in those stocks. At first they are careful to "maintain symmetry" as they put it, making certain that nothing they do on their second time through the day contradicts what happened the first time around. Eventually, though, they start to explore the limits of what they can do as far as changing the past and then things get interesting. Multiple viewings are almost required, because this film doesn't just hand you anything. You have to work for it, but the effort is quite rewarding.

Timecrimes (2007)

I caught this on DVD a few weeks ago and immediately thought it would go great on a double bill with Primer since both films take a particularly thought provoking look at time travel. This Spanish language film centers around a man named Hector who, while relaxing in his back yard, notices a woman in the nearby woods taking her clothes off. When he wanders off to get a closer he is stabbed in the arm by a man with pink bandages covering his face. Hector escapes and makes his way to a nearby building where a man suggests he hide inside a strange looking contraption. What Hector doesn't realize is this is a time machine and when he climbs out it is earlier that same day. Tellng any more would spoil the film and I highly recommend seeing it. Hector's motivations become a bit hard to figure out at times, but this is probably the most intriguing film ever when it comes to the whole time travel paradox thing.

The Butterfly Effect
(2004)
Ashton Kutcher gets a bad rap, mostly because he comes across as such a horse's ass. Maybe he actually is one, but who knows? I always liked him on That 70's Show, and in this dark tale of time travel which has really stuck with me. Kutcher plays Evan Treborn, a young man who has suffered from blackouts during traumatic events throughout his life and, at his psychiatrist's suggestion he has kept a detailed series of journals for years as a way of dealing with this. One day he learns that, by reading his journal entries of the time surrounding his blackouts, he can travel back to that point in time, inhabiting the body of his younger self for the short period that the blackout lasted. He uses this newfound ability to try helping his girlfriend Kayleigh (Amy Smart) who was abused by her father, but each attempt to change the timeline brings about one tragedy after another, including the loss of his limbs, giving his mother cancer, incarceration for murder and prison rape. The DVD carries a different ending from the theatrical version, though I have to say the latter made more sense to me. Not a feel good movie, but definitely an entertaining one.

Star Trek: First Contact (1996)
Star Trek and time travel are old acquaintances as is evident if you've seen Star Trek IV: The Voyage Home (the one with the whales) or J.J. Abrams's new Star Trek (the one with Winona Ryder). I settled on Star Trek: First Contact because, as a Trek fan, I loved how it used time travel to explore a pivotal point in the history of the mythos. During an attack on Earth, the cybernetic race known as The Borg travel back to the past to prevent the testing of the first warp drive that will lead to the formation of the United Federation of Planets. The U.S.S. Enterprise under the command of Captain Jean Luc Picard (Patrick Stewart) follows The Borg into the past to make sure history follows its original path. Picard and crew meet Zefram Cochrane (played with a boozy charm by James Cromwell) inventor of the warp drive and help him to complete his test flight. Meanwhile, The Borg have infested The Enterprise and the sexy and sinister Borg Queen (Alice Krige) has captured Commander Data and attempts to seduce him with the promise of adding organic components to his android body. This is one of the top three Trek films and easily the best of the ones that featured the cast of Star Trek: The Next Generation.

Army of Darkness (1993)

Although it's the weakest of the Evil Dead trilogy, it's still got Bruce Campbell in front of the camera and Sam Raimi behind it and that adds up to a whole lot of awesome. The previous film's battle with Kandarian demons known as Deadites sent the shotgun-toting, chainsaw-handed Ash (Campbell) hurtling through a vortex that landed him in medieval England. Now he must used his advanced weapons and a 1973 Oldsmobile to fight the legions of the undead -- to say nothing of his own stupidity -- to reclaim the Book of the Dead which will provide the power to send him back home. Probably my favorite bit in the film is when Ash must recite three magic words to steal the book back without alerting the Deadites. Our hero can't quite remember the whole incantation ("klaatu barada nikto" which is a nod to The Day The Earth Stood Still), so he mumbles something similar, takes the book, and allows the army of the undead to rise. Schmuck. This movie was a bit of a disappointment for me when I first saw it in the theater. Unlike the the other films in the franchise which were unrated, Army of Darkness was rated R so it doesn't deliver the over the top gore I had come to expect, but since then I've come to appreciate the film for what it is: a violent slapstick comedy with chainsaws, walking skeletons and Bruce Campbell. Who could ask for more?

How about you folks? What are your favorite time travel flicks?