The fate of the allied forces lies in the hands of Joanna and the Watsons in the next Daughter of Sherlock Holmes mystery from USA Today bestselling author Leonard Goldberg. During a critical stage in World War One, the Governor-General of South Africa journeys to London for a meeting of The Imperial War Conference. Days prior to the conference, the Governor-General is scheduled to have an audience at Buckingham Palace at which time a most precious blue diamond will be presented to King Edward as a symbolic gesture of the colonies’ resolute and never-ending allegiance to England. The flawless blue diamond, with its magnificent luster, weighs nearly 3000 carats which renders it one of the world’s largest and most valuable gems. On the Governor-General’s arrival, he is ensconced at the fashionable Windsor Hotel under the tightest security, with his entire entourage and formidable security team occupying the entire penthouse floor. All entrances and exits are locked down and closely guarded, and no one is allowed entrance after 6 PM. Despite the extreme precautions, the famous diamond is stolen from the Governor-General’s suite in the middle of the night, with no clues left behind. With Scotland Yard baffled, Joanna and the Watsons are called in to investigate the theft and it becomes clear that the crime is not simply the work of a master thief, but one that could greatly aid the Germans and turn the tide of war in their favor. Time is of the essence and the blue diamond must be recovered before it begins its travels which could cause irreparable damage to the allied war plans.

本作の真髄は、密室ミステリの様式美と世界大戦の激動が交錯する緊迫感にあります。巨大なブルー・ダイヤモンドが世界の命運を左右する壮大なスケールは、読者を論理の迷宮へ誘います。ホームズの血を継ぐジョアンナの冷徹な知性と、時代の暗雲を重ねるゴールドバーグの手腕は見事の一言に尽きます。 不可能犯罪の解明が諜報戦へ昇華される構成は文学的妙味の極みです。宝石の輝きの裏にある戦時下の狂気を抉り出し、論理の連鎖が国家を救う瞬間のカタルシスは圧巻。一刻を争うサスペンスの熱量に、あなたの知的好奇心は激しく揺さぶられるでしょう。