THE THIRD OMNIBUS OF AGATHA CHRISTIE'S 1920S NOVELS, COMPLETE WITH EXCLUSIVE BACKGROUND NOTES ON EACH ONE. THE MURDER OF ROGER ACKROYD Roger Ackroyd knows too much. He knows that the woman he loves poisoned her first husband to death. But upon hearing the news that she has taken her own life, he himself is stabbed to death. And so Hercule Poirot now faces his most demanding cast to date… THE BIG FOUR Hercule Poirot finds himself plunged into a world of international intrigue, pitting his wits against a ruthless plot of global proportions and risking his life to uncover the significance of 'Number Four'… THE MYSTERY OF THE BLUE TRAIN When the luxurious Blue Train arrives at Nice, the guard discovers of body of a brutally murdered woman whose priceless rubies are missing. As Poirot refuses to accept the guilt of the prime suspect, he begins an eerie re-enactment of the journey, complete with the murderer on board…