Gustav Hartmann is in trouble. Because of the new taxis he doesn't get many passengers in his horse-drawn carriage. To prove what he and his horse are capable of, he starts a trip from Berlin to Paris.

Then the spirit of Jack the Ripper seems to be very much alive in 1960s London as a series of brutal slayings by the Monster of London City has Scotland Yard baffled. In a macabre coincidence, a new play about the famous murderer is about to become a major West End hit... and the leading man is rapidly becoming the prime suspect!