Set in 1909 in Yorkshire, England, a coal mine has long relied on pit ponies to transport coal. When the mine introduces machinery to increase production and profitability, the ponies are deemed obsolete and slated for slaughter. Upon learning of this, three children devise a plan to rescue the ponies and release them.
Production
The film was based on a script by Burt Kennedy who had read an article about pit ponies in London. He wrote up a script and sold it to Ron Miller at Disney. Kennedy was a writer director but Miller felt he was better suited to Westerns and the film was given to another writer and director with whom Disney had deals. Kennedy called the movie " pretty good—not as good as it should have been, but it’s pretty good."