Stephen Sorrell, a decorated British army officer, returns home after the First World War to face unemployment, poverty and his wife's desertion. Determined to educate his son as a gentleman, Sorrell is forced to accept exhausting and demeaning jobs to provide him with the best possibilities for a brighter future.

Life as a private detective begins at 60 for this sprightly Lancashire housewife. Instead of winding down as her husband, Robert, expects, she's just getting started. Hetty takes a job to make ends meet and accidentally discovers her natural gift for sleuthing. In these first six episodes, she finds an eager sidekick in destitute teenager Geoffrey and puts her sensible pumps to the pavement in search of mysteries to solve.