Rowland Bates and his wife buy an old railway station which has been converted into a modern dwelling.
Bates, a steam train enthusiast, discovers that the railway line is still there, partly buried beneath the long grass and brambles, and with the help of three local children who call him 'Uncle Rollo', he uncovers the track so that it can be seen again, running past the 'station'.
They discover a rusty old guards van and an ancient steam engine, long abandoned, in a derelict corner of the property.
Bates wants to get publicity for return of the old countryside railways which were so savagely axed by the government of forty years ago. He takes on a retired engine driver, Edward Bere, or 'Teddy', to help get the engine going. He also discovers the railway line continues, still partly buried, across his neighbour's land, and he seeks permission to uncover the track over there, too.
His local M.P. is impressed and promises to raise question of opening some of the old country railway lines, thus giving the tourist industry and the public in general a wonderful alternative to travelling by car on overcrowded roads.
With the help of the three children, some friends and Teddy Bere, their gala day arrives with the opening of UNCLE ROLLO'S RAILWAY.