What if you could go back and change a crucial event in your life – right a wrong, fix something that was broken?

Evan Treborn (ASHTON KUTCHER) has lost track of time. From an early age, crucial moments of his life have disappeared into a black hole of forgetting. His boyhood is marred by a series of terrifying events he can't remember. What remains is the ghost of memory and the broken lives around him - the lives of his childhood friends, Kayleigh (AMY SMART) Lenny (ELDEN HENSON) and Tommy (WILLIAM LEE SCOTT).

Throughout his childhood years, Evan is under the care of a psychologist who encourages him to keep a journal, detailing the events of Evan's day-to-day life. While in college, Evan reads from one of his journals and finds himself thrust violently back in time. He realizes that the notebooks he keeps under his bed are a vehicle by which he can return to the past and reclaim his memories. But these recollections of violent, terrifying events, leave Evan feeling responsible for the damaged lives of his friends, particularly that of his childhood sweetheart, Kayleigh.

Evan decides to do something about it. He purposefully travels back in time, his present-day mind occupying his childhood body, in an attempt to re-write history and spare his friends and loved ones these traumatic experiences. By altering the events of the past, Evan hopes to transform the present. But his odyssey is a painful one.

Every time Evan changes something in the past, he returns to the present to find that his actions have unexpected and disastrous consequences. Try as he might, he can't seem to