When British Railways announce the closure of the Titfield to Mallingford branch line a group of local residents make a bid to run it themselves, backed by a monied member of the community who is attracted by the complete lack of licensing hours on trains. Unfortunately the local bus company starts to use methods that can hardly be seen as fair competition.

P.C. George Dixon is a long-serving traditional copper who is due to retire shortly. He takes a new recruit under his aegis and introduces him to the easy-going night beat. Dixon is a classic ordinary hero but also anachronistic, unprepared and unable to answer the violence of the 1950s.