"AM IN GREAT TROUBLE, please come at once. Duds."
It is the aftermath of the Second World War and Tommy and Duds Lethbridge have inherited a Manor House in Buckinghamshire. The couple invite their friends to an old-fashioned Christmas house-party to keep their minds off the dreariness of the times, England being still in the grip of post-war austerity.
The party begins favourably enough, though not much time passes before everything...