Night Train is the first song from the fifth series dedicated to the engines working during the night. The song is based on the post train theme from the third series which in turn is partly based on Thomas' theme. A version of the song with completely different lyrics that was in fact not about night trains at all, but rather about Thomas and Percy entering a mine, was heard in the Thomas Saves the Day live show. The original song was later re-released with a new CGI music video as part of Thom