For Jack Morrison (Joaquin Phoenix), that time has come. In a blazing 20 storey warehouse, Jack a member of the Fire Department's Engine 33 rescues a survivor from the 12th floor by lowering him out of a window in a heart-stopping sequence. Then, everything goes wrong when Jack falls through a hole and becomes trapped in the worsening inferno.

While the chief, Mike Kennedy (John Travolta) tries to work out how he and his men can rescue him, Jack reviews his past years as a fire fighter, shown in a series of flashbacks that are inter cut with his current life threatening situation during which he drifts in and out of consciousness and begins to run out of oxygen.

The flashbacks begin with his first day on the job, the ribbing and practical joking that is part of the ritual of welcoming a new arrival and the growing friendship between Jack and the other men of the fire house and with Kennedy who becomes his mentor. These are guys who share a special kind of bond and let off steam with some heavy after hours drinking. Jack becomes a husband and father when he meets and marries Linda (Jacinda Barrett), but inevitably, the good times are juxtaposed with tragedy and loss, and the perils of the job often put a strain on his family.

While Jack's life hangs in the balance, these memories and all that is important in his life and which has led him to his situation drift through his mind while the desperate effort to save him continues