The American ambassador’s voice was coming through the receiver.
He was supposed to keep talking.
Somewhere in the room, a hidden device was carrying his words to people outside. Security officer Joseph Bezjian needed time to find it without alerting whoever was listening. A note told Ambassador George Kennan to continue dictating.
The source turned out to be a wooden carving of the Great Seal of the United States.
It had arrived as a gift.
The Great Seal bug, nicknamed “The Thing,” was a Soviet listening device concealed inside that carving. It had no battery and no power cord. An outside radio signal activated it, allowing conversations in the room to be intercepted. When the signal stopped, the device became extraordinarily difficult to detect.
Someone had found a way to make a symbol of the United States listen for the Soviet Union.
The gift came from schoolchildren
On August 4, 1945, Soviet schoolchildren presented the carved seal to U.S. Ambassador Averell Harriman.
The United States and Soviet Union had been wartime allies. The gift appeared to be a gesture of friendship. The carving eventually hung in the American ambassador’s Moscow residence, where its hidden device was discovered in 1952.
I find the presentation almost as striking as the engineering.
A listening device needs a way into the room. This one came with a reason to display it. The eagle, shield, and familiar national symbol made the object suitable for an American official’s surroundings. The Markov case presents a darker version of the same concealment problem, involving the umbrella suspected as a delivery device.
The disguise didn’t depend on making it disappear.
It depended on making it belong.
That is a different kind of concealment from the hollow nickel that landed in a paperboy’s change. The coin survived by looking insignificant. The seal had a place of honor.
How could a listening device work without batteries?
The Thing was a passive cavity resonator.
That name sounds complicated, but its basic operation is understandable. Soviet operators directed a radio signal toward it from outside the residence. Sound in the room vibrated a thin membrane inside the device. Those vibrations changed the radio signal reflected back, allowing the operators to recover the conversation. For another documented example of radio used in intelligence communications, see radio used in intelligence communications.
The power came from outside.
There was no battery inside the carving that needed replacing and no cord running down the wall. The CIA describes it as a passive repeater activated by an incoming high-frequency signal.
A useful way to picture it is to think of the incoming radio signal as something the device could alter and send back. The room’s voices supplied the changes. The outside equipment supplied the signal and listened for its return.
It wasn’t a miniature tape recorder collecting everything for later.
It was a hidden path out of the room when the external equipment was operating.
The eagle had tiny openings beneath its beak
The International Spy Museum identifies tiny holes beneath the carved eagle’s beak as the openings that admitted sound to the membrane.
The vibrations inside then changed the returning radio signal.
That is the detail I would look for first if the carving were in front of me.
The face of the object was doing two jobs. It presented an American emblem to the people in the room while allowing their voices to reach the concealed mechanism.
The familiar expression “the walls have ears” becomes uncomfortably literal here. Nothing needed to move across the floor or reach beneath the desk. The object could remain where it was while people spoke around it.
Why didn’t a security sweep find it sooner?
An ordinary radio transmitter gives searchers a signal to find while it operates.
The Great Seal device depended on someone outside activating it. According to the NSA, switching off that external radio signal made the hidden bug virtually impossible to detect through its emissions.
That gave the searchers a timing problem.
Examining the room while the device was inactive could produce reassuring results without removing the threat. The absence of a signal at that moment did not establish that conversations were safe at other times.
This is what makes the design so unsettling. Its silence was part of its protection.
The ambassador’s dictation became bait
In September 1952, Bezjian investigated the ambassador’s residence, Spaso House.
An NSA historical account, based on a later discovery report, describes him staying there as an apparent houseguest. Equipment was brought in discreetly. Kennan then dictated a message as part of a planned test.
The searchers were trying to catch a listening device in operation.
Once the receiver picked up Kennan’s voice, Bezjian entered the room and followed the signal. The ambassador continued speaking while the search proceeded around him. The evidence led to the seal on the wall.
There’s real tension in that scene without adding anything to it.
Kennan needed to maintain the appearance of normal dictation. Bezjian needed to isolate the source. Whoever was receiving the conversation outside could potentially hear a careless remark announcing the discovery.
The room had become a trap for the people listening to it.
Finding it didn’t immediately explain it
Inside the carving was a device that challenged expectations about what a microphone and transmitter should look like.
American technicians called it “The Thing.” The International Spy Museum says British technical specialists took two months to work out its operation.
The design is credited to Léon Theremin, the inventor also associated with the electronic musical instrument bearing his name. Crypto Museum’s account describes his development of surveillance devices while working in a Soviet prison laboratory.
His instrument and the bug belong to very different settings, but both involved unusual uses of electronics.
One produced sound for an audience.
The other helped an unseen audience receive sound from a room it could not enter.
Was it listening for seven straight years?
The gift was presented in 1945, and the device was found in 1952. Those dates support the familiar description of a seven-year concealment.
They do not establish seven years of continuous listening.
An NSA historical account states that the precise date when the device began collecting American secrets has never been determined. That account also suggests the carving may have reached its permanent place in the residence in 1949.
The distinction changes the question.
Instead of imagining an uninterrupted recording, we should ask when the device was present, when the outside equipment activated it, and which conversations occurred during those periods.
The CIA acknowledges that the amount and content of compromised information are difficult to determine.
Discovery ended the immediate threat. It could not rewind every conversation that might already have escaped.
The gift returned during another spy scandal
On May 1, 1960, the Soviet Union shot down an American U-2 reconnaissance aircraft flown by Francis Gary Powers.
Later that month, Soviet representatives brought their accusations about American espionage before the United Nations Security Council. The United States answered with an object it had recovered years earlier.
On May 26, American representative Henry Cabot Lodge Jr. displayed a wooden replica of the seal and explained the listening device concealed in the original gift.
The connection to Powers also runs through the captured Soviet spy eventually exchanged for the U-2 pilot.
By then, the seal had changed roles. It had been a gift, a hiding place, and a source of intercepted conversations.
Now it was evidence displayed before the world.
Questions About the Great Seal Bug
Was The Thing a real Soviet listening device?
Yes. The NSA, CIA, and International Spy Museum document the device concealed inside the wooden Great Seal carving. It was discovered in the American ambassador’s Moscow residence in 1952.
Did the Great Seal bug need electricity?
It needed energy from an outside radio signal. It had no battery or wired power supply of its own. Calling it battery-free is accurate; calling it a device that needed no energy would be misleading.
Can you see the Great Seal bug in a museum?
The NSA’s National Cryptologic Museum documents a replica molded from the original carving, with a reproduction of the concealed mechanism. The International Spy Museum also identifies its displayed Great Seal equipment as reproductions.
Written under the pen name Evan Mercer for Stories in the Static, exploring real spy cases, hidden devices, and the evidence behind strange true stories.