The Tiflin family live in a remote ranch in the Salinas Valley in California. Tom Tiflin, a young boy, is given a small pony by his father, Fred Tiflin. His grandfather tells rambling and exaggerated tales of the west over meal times. Fred is tired of his stories but his daughter (Fred's wife) likes his eccentricity. Most of his stories revolve around his leading a wagon train cross country in the pioneer days.
Tom asks stable-helper Billy Buck (Mitchum) to help him raise and train the pony so that it can be ridden. Buck gives him a saddle and they name the pony Gabilan. Tom shows the pony to his young friends.
During a rainstorm, the pony escapes the stable and subsequently develops a fever. Despite Buck's efforts to nurse the pony, it develops strangles and requires a tracheotomy. Shortly after the procedure, the pony escapes from the farm. Tom follows the pony's hoofprints to a gully where it has died and is being eaten by vultures. He blames Buck for not saving the pony's life. Buck, feeling remorse, prepares to kill his own pregnant mare in order to give Tom a colt. Tom grows angry at Buck's willingness to sacrifice a horse and steals his knife. When they return to the stable, the foal has been born naturally, with both mother and colt surviving.
In adapting his novella into a screenplay, Steinbeck focused mainly on the chapters "The Gift" and "The Promise," and characters' names were changed from those in the book: Jody Tiflin became Tom and his parents Carl and Ruth became Fred and Alice. The film also features a much happier ending than does the novella; in the book, Billy Buck cannot deliver the foal naturally and kills the mare to perform a caesarean section to save the unborn foal. Other violent scenes, such as those in which Jody beats a vulture to death, were toned down or omitted entirely for the film adaptation.
In a contemporary review for The New York Times, film critic Bosley Crowther wrote: "[T]he story does ramble, and its several interlaced strands are often permitted to dangle or get lost in the leisurely account. An extraneous family situation involving the youngster's Ma and Pa, wherein the father has trouble with his ego, likewise confuses the plot. In directing the picture, Mr. Milestone has adopted a frankly casual style which further invests the proceedings with a languid quality."[4]
^Crowther, Bosley. The New York Times, "Red Pony, Based on Steinbeck Novel, New Bill at Mayfair -- Mitchum, Loy in Cast", March 9, 1949. Accessed: June 22, 2013.