The Horse Whisperer is a Western love story.  It recounts the healing of a traumatised horse, its troubled teenage owner and her unstable family.

On a snowy morning in upstate New York, Grace and her friend Judith go riding. A slip on an icy slope slides them into the path of an oncoming truck. Judith and her horse die in the collision, whilst Grace and her horse Pilgrim survive with deep mental and physical scars. Grace loses a leg and has to learn to walk again with a prosthetic; Pilgrim undergoes extensive surgery and starts exhibiting dangerous behaviours. Grace's parents are Annie, a successful, workaholic magazine editor, and Robert, a lawyer.  They cope in different ways with their daughter's accident and their relationship suffers.

The people charged with Pilgrim’s care are scared of his newly violent behaviour and treat him cruelly. Annie refuses to have the animal put down, and searches for a way to ‘fix’ him. She hears of a ‘horse whisperer’ called Tom Booker and undertakes a marathon journey from New York to his home in Montana, dragging Grace and Pilgrim with her.

Annie and Grace’s relationship is volatile, and Grace punishes her mother by refusing to talk to her. In Montana, as Tom works with Pilgrim, Grace and Annie slowly heal too, coming to love the ranch way of life. Grace gets the courage to ride again and Annie starts to let go of her obsession with work. Annie and Tom are drawn to each other, a fact which does not go unnoticed by Tom’s sister-in-law, Diane. When Grace briefly returns to New York for a prosthetic fitting, Annie and Tom are left alone on the ranch. In the few days they have together, they fall deeply in love.

Grace returns to the ranch and, with Tom's help, attempts to ride Pilgrim. But the horse is still unwilling and Tom is forced to undertake drastic measures, making Pilgrim lie down and telling Grace to stand on him. The unusual therapy is successful, and Pilgrim allows Grace to ride him.  The two crash victims are finally healed.

At their leaving party, Grace overhears a conversation between Diane and her husband and learns about Tom and Annie's affair.  Devastated, she rides out alone into the wilderness. Tom rides after her and finds her surrounded by a group of mustangs.  Pilgrim is fighting a wild stallion. Tom saves Grace and Pilgrim, but sacrifices himself: he is struck by the hooves of the stallion and killed.

Grace and Annie return to New York to rebuild their life with Robert.  As a final complication, Annie discovers that she is pregnant, giving birth to a baby with Tom's blue eyes.