The closing of a railway line by the government, which hopes to substitute a bus line for the rails, arouses the town of Titfield, and the citizens open the battle by taking over the train themselves. The bus company officials wreck the train one night, ruining the villagers' enterprise.
But wait! The wily inhabitants bring out an old engine, The Thunderbolt, from the village museum and make a triumphant run for it. Rich in laughs and rustic scenery.