Two engineers, Aaron (Shane Carruth) and Abe (David Sullivan), are performing experiments in Aaron’s garage, hoping to make it big. They are trying to reduce the weight of objects by electromagnetic means. When a watch is left inside the field, they discover that it speeds up or reverses time as well. Abe builds a stable time-travel apparatus big enough for a human being, and travels six hours into his own past. He has to hide himself in a hotel room to avoid coming into contact with himself. Abe brings Aaron to the scene and together they watch his earlier self enter the box.
Over several days, they move back and forth, dabbling in the stock market and making money. Their contrasting personalities—Abe is cautious and a control freak, Aaron is impulsive and meddlesome—cause emotional friction as the time travel and the 36-hour days play havoc with their bodies. Aron’s ears begin to bleed and his handwriting becomes illegible. One night, a late-night encounter with Thomas Granger (Chip Carruth), the father of Abe’s girlfriend Rachel (Samantha Thompson) causes serious trouble. Thomas has been in the box and he falls into a comatose state. Abe comes to think time-travel is too dangerous and he enters a second box to travel back and stop the experiment before it starts. Future Abe sedates original Abe to stop him but finds that Future Aaron has gotten there first. Future Abe faints dead away.
Briefly reconciling, they travel back in time together and change the timeline at a party where Rachel was nearly killed by a gun-wielding party-crasher. Aaron stops the gunman and becomes a hero. Abe and Aaron break off their relationship. Aaron wants to travel to foreign countries and make a fortune, while Abe wants to stay in town and sabotage the original box. Abe warns Aaron to leave town and never come back. There seems to be more than one Aaron at large. One future-Aaron has shared his knowledge with one original-Aaron. Future Abe, moreover, is watching original Abe to keep him ignorant of the future. One of the Aarons is secretly building a box the size of a warehouse.
This is an independent, experimental, low-budget film, directed, produced, edited, and scored by Shane Carruth, who plays Aaron. Everyone in it is a friend or a relative. Carruth consciously decided not to simplify the plot or the time-travel theory for the audience--he is both a mathematician and an engineer—and audiences were quite often confused, but critics were wowed by its sheer byzantine intellectual rigor, and it won a Grand Jury Prize at the 2004 Sundance Film Festival.
It only made a little more than half a million dollars at the box-office, but it cost only 7000 dollars to create, mostly in film stock. Now it is, of course, a cult film. The math behind the theory was inspired by Richard Feynman, who demonstrated that the interaction between particles happens both forward and backward in time. Rian Johnson, the writer and director of Looper (2012) sent his script to Carruth for comment and was told that his time-travel was all wrong. Abe’s last name is Terger, which is regret going backwards.