Christmas Past, Christmas Present - S0.E1

Richard Forrest is Mrs Peacock's guest for Christmas dinner. His father, a retired judge, is the previous owner of Arlington Grange, and Richard hopes to get the estate back for himself. It transpires that several of those present have appeared in the dock before Judge Forrest, and Forrest Junior has blackmail in mind. A dead body, predictably, is soon discovered - but it isn't Forrest's, it's the body of Ken, the chauffeur. All must soon be revealed...