Detective Inspector Campbell (Gordon Jackson) looks into the murder of a teacher at a girls school where there are a number of suspects, including her colleagues and the married man she had been seeing.
Private eye Edward Mercer travels to Venice to locate a man due a reward for his aid in the war. Shortly after arriving, he becomes the prime suspect in the murder of his local contact. In his quest to clear his name, Mercer uncovers a conspiracy. Even the local magistrate seems to be working against him, and Mercer begins to suspect the man he came to find is behind it all.
A modern-day retelling of Arnold Bennett's novel, in which a Treasury official with a reputation for fiscal prudence is left a great deal of money and has no idea how to cope with sudden personal wealth.
