N or M? (+CD)

'Key is in the lock all right, sir. On the inside. Mr Ackroyd must have locked himself in.' Poor Roger Ackroyd. He knew that the woman he loved had been harbouring a guilty secret - she poisoned her first husband. And yesterday she killed herself. But guilty secrets rarely stay secret. Who had been blackmailing her before her death? Had it really driven her to suicide? And would it all be revealed in the letter that arrived in the evening post? Sadly Roger Ackroyd wasn't going to...

"Anyone who murdered Colonel Protheroe,' declared the parson, brandishing a carving knife above a joint of roast beef, 'would be doing the world at large a service!' It was a careless remark for a man of the cloth. And one which was to come back and haunt the clergyman just a few hours later. From seven potential murderers, Miss Marple must seek out the suspect who has both motive and opportunity.

A flamboyant party host is murdered in full view of a roomful of bridge players… Mr Shaitana was famous as a flamboyant party host. Nevertheless, he was a man of whom everybody was a little afraid. So, when he boasted to Poirot that he considered murder an art form, the detective had some reservations about accepting a party invitation to view Shaitana's private collection. Indeed, what began as an absorbing evening of bridge was to turn into a more dangerous game altogether…

On a French golf course, a millionaire is found stabbed in the back. An urgent cry for help brings Poirot to France. But he arrives too late to save his client, whose brutally stabbed body now lies face downwards in a shallow grave on a golf course. But why is the dead man wearing his son's overcoat? And who was the impassioned love-letter in the pocket for? Before Poirot can answer these questions, the case is turned upside down by the discovery of a second, identically murdered corpse.

When the luxurious Blue Train arrives at Nice, a guard attempts to wake serene Ruth Kettering from her slumbers. But she will never wake again - for a heavy blow has killed her, disfiguring her features almost beyond recognition. What is more, her precious rubies are missing. The prime suspect is Ruth's estranged husband, Derek. Yet Hercule Poirot is not convinced, so he stages an eerie reenactment of the journey, complete with the murderer on board.

'Oh, well, everyone has to die sometime. I never worry over people dying...' When socialite Lucy Angkatell organises a weekend's entertainment at her English country house, The Hollow, it seems she has thought of everything: the capable butler, the requisite number of kitchen maids - in fact, the only thing she seems to have overlooked is the fact that most of her guests hate each other. A far-from-warm welcome greets Hercule Poirot as he arrives for lunch. Instead, a man lies...