This event took place in February 1945 during the Yalta Conference in Crimea. While the state leaders discussed the post-war world order, several foreign diplomats visited the All-Union Children’s Camp “Artek,” which was celebrating its 20th anniversary. The Soviet special services were interested in the American ambassador, Averell Harriman. They knew he collected handicrafts made of rare woods and prepared a special gift for him – a wooden US coat of arms. During the ceremony, the pioneers performed the American anthem and then presented the emotional diplomat with the coat of arms. When Harriman asked, “Where can I hang this wonder?” someone from the Soviet delegation suggested placing it in his office, to the envy of the British. The Americans checked the item for bugs but found nothing. However, the bug was indeed there, just extremely difficult to detect. The listening device “Zlatoust” did not require a power source and was activated only by a powerful radio signal from equipment in a neighboring building. “Zlatoust” functioned practically like a mirror reflecting light. During conversations in the office, its thin film membrane vibrated under the influence of sound waves and modulated the reflected signal, which was captured by a special receiver of the Soviet special services. It wasn’t until 1952 that the Americans discovered the bug. The Soviet technology impressed them so much that they immediately started creating their own versions.