Foyle suspects an illegal fuel racket when a truck carrying barrels of petrol crashes. Sam convinces Foyle to let he go undercover at the fuel depot, but what she learns may be very bad for Foyle's son Andrew.
Foyle's War opens in southern England in the year 1940 - which may seem a strangely remote period in which to place a new detective, but the setting turns out to be a means of adding moral and dramatic depth to the storylines.
Christopher Foyle is a police inspector frustrated at being stuck at home investigating provincial crimes during the second world war.
Honeysuckle Weeks is an inspired choice as Foyle's sidekick, a clergyman's daughter posted from the Women's Royal Army Corps to serve as his driver, and she plays the part with an admirable period style.