The book "Сверкающий цианид" — Агата КристиСверкающий цианид. За год до описываемых событий, в ноябре, семь человек собрались в ресторане "Люксембург" на обед. Одна из них, Розмэри Бартон, умерла прямо за столом. Как выяснилось позже, она отравилась цианистым калием, а причиной самоубийства стала депрессия. Её муж получает анонимное письмо, в котором утверждается, что Розмэри была убита, и Джордж решает выяснить всё до конца. Он приглашает в тот же ресторан всех участников того злополучного обеда. Актрису, удивительно похожую на его покойную жену, он просит сыграть её роль. Однако актриса так и не пришла, а Джордж погибает от того же цианида, подсыпанного в бокал. Его смерть тоже посчитали бы самоубийством, если бы не друг Джорджа, полковник Рэйс, и агент тайной полиции Энтони Браун. Они выяснили, что целью убийцы была Ирис (Айрис), 18-летняя сестра Розмэри, которая является единственной её прямой наследницей.
One year ago on 2 November, seven people sat down to dinner at the restaurant "Luxembourg". One of them, Rosemary Barton, never got up. She was thought to have committed suicide due to post-flu depression. Her husband, George Barton, received anonymous letters saying that Rosemary did not kill herself but was murdered. George started to investigate and decided to reconstruct the dinner at the same restaurant, inviting the same people as well as an actress who looked like his late wife. The actress did not arrive and that night George died at the table – poisoned, like his wife, by cyanide in his glass. His death would have been dismissed as suicide as well if not for the investigation by his friend Colonel Race. During the investigation it is revealed that the intended victim was Rosemary's younger sister Iris, whose glass was confused with that of George by a careless waiter. Due to a stipulation of her uncle's will, as Rosemary died childless her inherited fortune passed to her teenage sister when she died. If Iris had died at the table as intended, the money in turn would have passed to her aunt Mrs Drake, a decent person but one who is utterly manipulated by her rotter of a son, Victor, who threatens to commit suicide when he needs money from her. Colonel Race and Iris's suitor, Anthony Browne, discover that Victor had planned the murder together with his lover Ruth Lessing, George's secretary. (Note that Christie named the ruthless female conspirator "Ruth Lessing"; an inside joke, no doubt. ) The plan failed because when the group went to dance Iris dropped her bag and a waiter, retrieving it, misplaced it at another seat before everyone came back from dancing. When the companions returned to the table, they all sat one seat askew due to the misplaced bag, which is why George sat at Iris's original seat and drank the poisoned champagne meant for her. To confirm the suicidal nature of the death, Ruth had planted a pack of cyanide in Iris's bag and Victor had disguised himself as a waiter to poison the champagne. When this failed, Ruth attempted to run Iris over with a car. Eventually, Colonel Race, together with the police and Anthony Browne, unravel the truth and save Iris from Ruth, whose last attempt at killing Iris by knocking her unconscious and setting up a fake suicide by gassing scenario almost succeeds. The anonymous letters to George it turns out had been sent by Ruth to convince him to re-stage the dinner at the Luxembourg so that Victor and Ruth could kill Iris. | 
