A lavish weekend party sees Miss Marple accompany Lady Virginia Revel to her family home of Chimneys - a house which was once prized for its diplomatic gatherings until a rare diamond was stolen from the premises over twenty years ago. The tenacious career politician, George Lomax, has persuaded Virginia's father, Lord Caterham, to host an evening for an important Austrian Count, Ludwig Von Stainach. Virginia, the daughter of Miss Marple's late cousin, must decide by the end of the weekend whether to accept a marriage proposal from George Lomax or to follow her heart and the courtship of another more adventurous suitor, Anthony Cade. Dismayed by the odd array of guests, including socialist spinster Miss Blenkinsopp, Caterham's formidable eldest daughter Bundle and the quietly inscrutable maidservant Treadwell, Lomax castigates his affable assistant Bill Eversleigh, who also has a soft spot for Virginia. It becomes apparent that Count Ludwig has taken a personal interest in Chimneys.