As WW2 rages around the world, DCS Foyle fights his own war on the home-front as he investigates crimes on the south coast of England. Foyle's War opens in southern England in the year 1940. Later series sees the retired detective working as an MI5 agent operating in the aftermath of the war.

A pregnant woman and her husband are taken in by a farmer and his wife after crashing their car in the Scottish countryside. Once inside, they realize their hosts’ daughter is a missing child from the news years earlier. Things take a sinister twist when the farmer and his wife inform the couple they intend to keep their baby once born.