The old steam engine of the Valsugana railway line is going to retire and will be replace by modern diesel locomotive. Through the smoky scenes of its last run, a television service recounts part of the story of this important and glorious railway line: from the official opening day to the records of the "belle epoque", to the days of the teo world wars, always at the service of mankind and goods. The Valsugana Express, similar to, or rather poor sister of the glamourous Orient Express, will continue to be a useful mountain railway even in the eighties. The firs step to modernization is this change in the engine which marks the end of an era.