The Tragedy at Marsdon Manor

Marsdon Manor comes with its own ghost story, which is convenient for everyone except the dead man. Poirot is called in over a death on the estate that looks less like violence than like fright: the victim appears to have been scared out of life by the spirits said to haunt the grounds. It is the kind of case a rational detective should be able to dismantle in an afternoon. But then the situation tilts. The staged mystery he was asked to solve turns out to be a cover for something real, and a genuine killing follows nearby, which changes everything about the manor's carefully arranged atmosphere. The victim's fear becomes a clue in itself, the sort of detail Poirot never lets go of.

The household closes ranks around him: Jonathan Maltravers (Ian McCulloch) and his sister Susan (Geraldine Alexander), Captain Black (Alastair Duncan), Miss Rawlinson (Anita Carey), Samuel Naughton (Desmond Barrit), Danvers (Ralph Watson), Dr Bernard (Edward Jewesbury). Hastings is along, Japp arrives to do the official work, and Poirot walks the line between gothic melodrama and plain human greed.

David Renwick wrote the script with Agatha Christie, and Renny Rye directed. The manor is a lovely bit of television real estate, all shadows and good furniture. Ian McCulloch gives Jonathan Maltravers a haunted quality that keeps you guessing about the haunting.

The episode does something sly with the ghost story. It lets the supernatural claim stand long enough to be useful, then sets it aside. The real horror is the usual one: people who want things and will arrange deaths to get them. Poirot clears the spirits and finds the flesh-and-blood culprit, and the manor settles back into its quiet, which is not quite the same as peace. It is one of the more atmospheric entries in the run, and the atmosphere earns its keep.