Eric Lomax, a former British Army officer, is haunted by traumatic memories of being a prisoner of war in a Japanese labor camp during World War II. After the war, he struggles with PTSD, which severely affects his daily life and personal relationships. He meets Patti, a fellow train enthusiast, and the two quickly fall in love and marry. However, Eric's severe emotional scars soon become apparent, causing strain in their marriage. Desperate to help her husband find peace, Patti reaches out to Finlay, a fellow POW and close friend of Eric's, to uncover more about his harrowing past and the specific events that continue to torment him.

Through Finlay, Patti learns about the torture and suffering Eric endured while working on the notorious Thai-Burma railway. Eric's pain is compounded by one particularly cruel Japanese officer responsible for much of his suffering. Determined to confront his past, Eric decides to return to Thailand with a grim resolve. What follows is a gripping journey of confrontation and reconciliation as Eric faces the ghosts of his past and strives to find closure.