The plot of "Black Beauty" follows the titular horse's life after she is captured from the wild. After forming a deep bond with Jo Green at Birtwick Stables, their idyllic life is shattered when the stables close, and Beauty is sold. This separation is the central conflict of the film, leading Beauty through a series of different owners and experiences that highlight both human kindness and cruelty.
She is first sold to a park ranger named Terry, with whom she undertakes dangerous rescue missions. After Terry's retirement, she is passed to a farmer who works her hard with old equipment. Subsequently, she is sold into the life of a New York City carriage horse. It is here that she has a heartbreaking, brief reunion with her old stablemate, Ginger, only to witness Ginger's death shortly after, a direct and somber moment taken from the novel. Beauty's condition deteriorates under a cruel owner until a kind stable boy, Manuel, alerts the authorities to the abuse. This act of kindness leads to her rescue.
The climax of the film is the long-awaited reunion between Beauty and Jo. Several years have passed, and Jo has spent that time searching for her beloved horse. In the end, it is revealed that Jo, now an adult and married to the kind-hearted George Winthorp, has bought and restored Birtwick Stables, turning it into a permanent home for rehabilitated horses. She brings Beauty back to this sanctuary, where they are also reunited with Merrylegs. The film concludes as the novel does, with Beauty living out the rest of her days in peace and happiness, surrounded by those she loves, finally home.