The film begins with Jack Starks, portrayed by Adrien Brody, serving as a soldier during the Gulf War in 1991. His voice-over reveals a haunting truth: he died for the first time at the age of 27. While on duty, a startling encounter with a young boy leads to him being shot in the head.
Fast forward a year, and Jack is a solitary figure hitchhiking along a snow-covered road. He stumbles upon a broken-down pickup truck belonging to Jean Price (Kelly Lynch), a young mother who appears to be under the influence of drugs or alcohol, with her young daughter alongside her. As Jean vacillates between reality and her haze, the young girl engages in cheerful conversation with Jack. He showcases kindness by attempting to fix the truck and ends up giving the girl his army dog tags, a gesture that surprises both the girl and Jean. When the truck miraculously starts, Jean wrongly perceives Jack as a threat due to her delusions, compelling her to hastily leave with her daughter, despite the girl’s protests.
Later, Jack gets a ride with a stranger, but their drive takes a dark turn when they're pulled over by a policeman. Although the incident is shrouded in mystery, the narrative jolts forward, and we find Jack on trial for the cop's murder, unable to recall any details of that fateful day except for his encounter with Jean and her daughter—who remain untraceable.
Declared guilty but insane, he is sent to an asylum overseen by Dr. Thomas Becker (Kris Kristofferson). Here, he meets Dr. Beth Lorenson (Jennifer Jason Leigh), who struggles with her own work-life balance outside the asylum, as she attempts to help a disabled boy—struggles Jack is unaware of.
One fraught night, Jack is immobilized with drugs, placed in a straight jacket, and confined within a mortuary drawer. This leads to a barrage of rapid flashbacks filled with memories of his past, including the war and the deadly incident with the policeman. Determined to evade his confinement, Jack feigns compliance, only to later lash out at Dr. Becker.
In an unexpected twist, Jack finds himself outside a diner late on Christmas Eve, where he meets Jackie Price (Keira Knightley). She offers him a ride home, revealing her struggles with alcohol and an isolated life after losing her mother in a tragic fire. While they share toasted sandwiches and fleeting moments of connection, Jack discovers the dog tags he gave the girl all those years ago and realizes he has somehow jumped forward in time to 2007. With a desperate urge to explain his situation to Jackie, Jack faces disbelief when she insists he died on January 1, 1993, due to a head injury. Confusion mounts, especially as Jackie becomes more unstable upon hearing Jack’s story, prompting him to leave.
Jack then wakes up back in the mortuary drawer in 1992, determined to revisit the future enough times to piece together the events doomed to unfold on January 1st. In a thrilling turn of fate, Jackie ultimately believes Jack’s claims and agrees to help him decipher his own history. They both venture to meet Dr. Beth Lorenson, whose insights on past traumas lead to revelations about Jack’s own mysterious death.
Through a mix of past and future encounters, Jack unravels the sequence of events surrounding that tragic day. He learns about the circumstances of his accidental shooting and, armed with knowledge, tries to save Jackie from the foretold fate of her mother. With persistence, Jack manages to convince Dr. Lorenson to implement an experimental treatment on the boy she was caring for, leading to significant breakthroughs in therapy.
Triumphantly, Jack enacts a plan to deliver a warning letter to Jean Price, hoping to alter the tragic fate that awaits her. However, as Jack returns to the asylum, a slip on the ice results in the accident that ultimately leads to his demise. Despite this, the magic of time reclaims him, sending him back to 2007 where Jackie awaits, rejuvenated by the hope Jack provided her mother. As they drive off together, Jackie’s question “how long do we have?” hangs in the air, underscored by the music echoes of “We Have All The Time In The World.”
