Can Dora and Rex solve this cold case without ending up in hot water?London, 1923. In a Mayfair dining room, Theodora Laurent and Lord Rex Bankes-Fernsby make an incredible discovery. Rex's sister Caledonia is a naturally gifted codebreaker. Upon hearing this news, Lord Audley, London's spy master, asks for their help with a most unusual mission. Twenty-five years earlier, his wife died in a terrible accident. Now, he has uncovered evidence that her death may have been murder. The answer lies in...