Sad Cypress

Five days. That is the deadline Poirot is given in this one, and it is a nasty little countdown, because the case looks closed before it starts. Elinor Carlisle is accused of a double murder: her ailing aunt, Mrs Welman, and Mary Gerrard, the beautiful young woman who broke up Elinor's engagement to Roddy Winter. Everything points at Elinor, and she is the obvious culprit in exactly the way that should make Poirot uneasy. The cypress of the title is a funeral tree, which tells you the tone from the start.

But he spends the five days circling a household full of people who would rather he did not. Dr Peter Lord has his own feelings about Elinor; Nurse Hopkins and Nurse O'Brien saw more than they admit; Ted Horlick loved Mary; Marsden is the family solicitor; and Mrs Welman's illness left everyone waiting for her money and her death. Nobody in the house looks sorry, which is its own clue. The household runs on routines that a murderer would find very convenient, and Poirot notices every one of them. The closer he looks, the less simple the case becomes.

Elisabeth Dermot Walsh plays Elinor and carries the weight of the suspicion well. Rupert Penry-Jones is Roddy Winter, Kelly Reilly is Mary Gerrard, Paul McGann is Dr Peter Lord, Phyllis Logan is Nurse Hopkins, Marion O'Dwyer is Nurse O'Brien, Diana Quick is Mrs Welman, Stuart Laing is Ted Horlick and Jack Galloway is Marsden. Agatha Christie and David Pirie wrote it, David Moore directed, and David Suchet is Poirot.

The trial hanging over the story gives the episode an urgency the drawing-room mysteries lack. He is clearing a name against the clock, with a life in the balance. The case is built from a will and a household, with one young woman in the dock while the clock runs down. It is a quiet, cold piece of work, and the chill is the point.