Incredible Secret Spy Devices of History

Spy movies have given us a strange look into spy devices. From very dangerous weaponized umbrellas to exploding bats, let’s explore some of the most incredible – and unbelievable – tools and methods used by spies in order to complete their missions.

10. Animal Instincts

When most of us think of spies, we picture sharply-dressed, pistol-holding smooth-talkers. We don’t picture pigeons. But, as it turns out, perhaps we should. As far back as the times of Ancient Rome, important people used pigeons to pass secret messages between themselves.


These common birds have an incredible innate homing ability directing them to places over a thousand miles away.  They have continued to be some of our best undercover agents ever since. During the First World War, they strapped pigeons with small, basic cameras and sent them into enemy airspace.


After a controlled time-delay, the camera would snap pictures of enemy bases from above, providing invaluable military info. British intelligence services at the time even considered strapping explosives or biological weapons onto them so they could be detonated on target locations.

But Pigeons aren’t the only species that people have used to spy on each other. There have been countless instances of humans using animals’ innate abilities and senses to our advantage. The next agent of animal deceit is the common housecat. Known officially as ‘Acoustic Kitty’, a CIA operation during the Cold War involved implanting a radio transmitter, a microphone and an antenna inside the body of a cat.

©Wilson Rothman

They send the cat – still alive – into the vicinity of two Soviet suspects. They hoped that it would record their conversation. Sadly, a car allegedly hit and killed the cat soon after they released it. The ethics of the case have been a matter of concern in recent years. But the difficulty of making a cat obedient enough to carry out the work of spies has cemented this case as one of the most bizarre failures of its kind.

©New York Post

9. Secret Tools for Survival

Being captured as a spy can leave you in a tight spot. Which is why some ingenious spy devices and methods have been used in the past to help spies survive tough situation. But the solutions weren’t always… pleasant. Case in point: the CIA’s Cold War concealed survival kit.


This kit was designed to be thoroughly hidden in case of searches. Can you guess where? A worryingly-large pellet was kept inside the user until they were able to pass it safely. After passing they would – presumably – clean it off a little, before cracking it open and retrieving the tools and weapons inside.

8. Fun and Games

Being a prisoner of war in Nazi Germany was about as far from a fun experience as possible.

©Everett Historical

But, as part of the strange logic of the Nazi leadership, prisoners of war were allowed to receive games and pastimes from humanitarian groups like the Red Cross. Seizing on this opportunity, allied forces began shipping modified versions of Monopoly to POWs.

©Łukasz Niedzielski 

Shallow indentations were cut into the board to hide tools and maps. Some of the playing pieces could also be re-purposed as tools. Sometimes, there was even real money hid in amongst the Monopoly money.

7. All Mapped Out

Monopoly boards weren’t the only places where vital escape tools were hidden for spies in the twentieth century. Prisoners of War often received harmless-looking decks of cards that – when wet – could be peeled apart to reveal a map of the local area.

 This would have been incredibly useful for any escape attempts, as many prisoners found themselves in totally unfamiliar territory. For those looking to keep as low of a profile as possible, a unique spin on a classic idea became available during World War 2: silk maps.


No, these aren’t meant to be worn as a nice soft scarf, though I’m sure they’d serve that purpose fine too. These maps were crafted out of soft fabric for several reasons: they wouldn’t deteriorate in the rain like the paper maps, nor would they tear easily. Most importantly, they did not rustle – an easily neglected but hugely important factor in remaining undetected.

6. Spy-Tech

Spy technology has come an incredibly long way in the past 100 years. It evolved from very basic, low-quality microphones and cameras, into the drones, phones and always-listening Google homes we see today. Modern technology can achieve incredible feats, like the cleverly hidden cellular interception rucksack.


It looks like a normal backpack but has the incredible technological ability to intercept up to 30 phone calls at the same time. But even as early as the mid-twentieth century, we were achieving some great progress in the world of espionage. The microdot camera was a brilliant example of secretive genius.

©International Spy Museum

The tiny camera, perfected in the 1960s, could photograph sensitive documents and reduce the image to the size of a pinprick. These could later be viewed using a microscope. This meant that confidential images could be easily snuck away, due to their tiny size.

5. Hideaway

Sometimes, as a spy, you pull the short straw and end up on hideout duty. This isn’t usually the cop- drama, sitting in a car with coffee and donuts, waiting for the perp to arrive, type of situation.

A CIA espionage guidebook, ‘The Official CIA Manual of Trickery and Deception’ advises on a clever method. However, it’s a rather claustrophobic method of concealing a spy in a vehicle, for surveillance of the vehicle’s owner. This involves modifying the fuel tank so that one half is empty. The unlucky spy has to reserve themselves a very cozy spot in the vehicle that’s accessed through a hidden compartment in the boot. 007 doesn’t know how lucky he is.


But spying often involves the hiding of a different kind. Throughout history, intelligence gatherers have fallen over each other trying to ensure the safe transport of secret messages and items. Even as far back as the regal courts of Queen Elizabeth I in England, her trusted spymaster was able to intercept coded messages transported in beer barrels. Due to his findings, and decoding abilities, Sir Francis Walsingham was able to thwart a major assassination plot against his Queen.

©John de Critz

4. Making Invisible Visible

Secret messages don’t always reach their target. Interception is something that most secretive organizations prepare for. They do it in some pretty clever ways. Invisible ink is one such practice.


You may be surprised to find that this is not a particularly recent invention. Records indicate that invisible ink was being used as far back as the fourth century BC. One of its famous more recent proponents was none other than George Washington. Washington used a special type of ink that could only be made visible with the use of a secret and specific second chemical. The name of the chemical is still classified to this day.

As shown by the craftiness of Francis Walsingham, spies have always been gifted interceptors too. While developments in spying have led us to some pretty uncomfortable places (like the nosy NSA), they have also given us some very unique inventions, like this ‘envelope x-ray spray’.


This spy device allows you to peek inside at the contents of an envelope for a moment before the transparency fades away moments later. So, be careful what you’re sending in the post – you never know who might have a can of this stuff just waiting to be sprayed.

3. Code to Victory

Of course, one of the smartest ways to keep your message from being read by someone who isn’t supposed to read it, is to translate it into a secret code. This method has been dated as far back as Ancient Greece and beyond, with the use of scytales.

via Wikipedia

In this era, military leaders pass ribbons inscribed with seemingly-random alphabetical characters between themselves. leaders. When the ribbons were wrapped around a block of a specific size and shape – of which both the sender and recipient would have safely locked away – the letters would align to spell out critically-important messages regarding military plans and information.

Things have become infinitely more complex as time has passed. Particularly with the development of computers, which can generate encryptions that are near-impossible to crack. Similarly, advancements in manufacturing have allowed for the production of sneaky objects like this compact mirror, another brainchild of the CIA.

©Central Intelligence Agency

Useful for powdering your nose, the hidden secret of this little looking-glass is revealed when tilted at just the right angle – if done correctly, a secret code is revealed.

2. Killer Accessories!

It’s no secret that the life of a spy can involve regular brushes with death. Sometimes, in following orders, a spy must carefully and untraceably take out a target. License to kill, and all of that. Ingenious inventions such as the CIA Stinger, a 22-caliber single-bullet firing device concealed within a toothpaste tube, are able to remain undetected as part of an agent’s travel bag.

©Drop Todorov

I just hope no one ever tried to squeeze this one on to their toothbrush – that’s a dentist bill no one wants to pay. Similar inventions were common in the mid-twentieth century, like the Sedgley Fist Gun, with probably the coolest weapon name ever.

©Rock Island Auction Company

The glove would fire a single round when the wearer curled their hand into a fist, delivering an unexpected and lethal blow to the unfortunate target when punched. But perhaps the most bizarre of all is the Bulgarian Umbrella.


A pellet of ricin, a lethal and almost untraceable poison, would sit in the tip of the umbrella. A person can inject it into a victim with the flick of a switch on the umbrella’s handle. In fact, even the US department of defense has experimented with hidden weapons inside umbrellas. Charles Senseney, a former weapons developer for the DOD testified to the Senate intelligence committee that he designed one for them that could fire darts. He spoke out in regards to the killing of JFK, who many believe was killed by this type of spy device. The reason for that is the strange man holding an umbrella near JFK when he was assassinated, despite the fact it wasn’t raining.


Though unconfirmed, there’s definitely a trend for putting weapons in items as mundane as possible; as these are the last things that a target would perceive as threatening or suspicious, which is what makes them so effective.

1. Boom for Improvement

One of the central principles of being a good spy is going unnoticed. Sometimes, though, history has shown that secret organizations can lack a certain… subtlety, at times. And sometimes, spy plots can go explosively wrong. Granted, the use of explosives in secret operations has had some success, like nineteenth-century coal torpedoes, utilized during the American Civil War.

©Edward H. Ripley

These were designed to blend within real coal and were thrown into the furnaces of Union steam transportation vehicles. They would explode, killing crewmen and passengers, and leaving the engines out of action. For the most part, however, spies and explosives don’t tend to mix too well. The CIA tried to use poisoned and explosive cigars to assassinate Fidel Castro but failed repeatedly. Castro was clearly up to date on his cartoons.

©The Economist

Not even sweet, delicious chocolate was safe from the busy fingers of spies in the Second World War. In a bizarre turn of events, British intelligence found elaborate designs for an explosive chocolate bar– made with real, edible chocolate.

©Ulrike Mai

It was discovered to be part of a wider plot to assassinate prime minister Winston Churchill. Luckily for Churchill, the plan never came to fruition. However, the result would have been more than a toothache. Once the bar had been broken, with the classic, satisfying pop, a short fuse would activate. After that, the chocolate bar’s lethal payload would detonate. It will surely do some serious damage to anyone in the surrounding area.

Unfortunately, our animal friends haven’t been too lucky in the field of explosive espionage, either. In perhaps the most baffling of all espionage tactics which was unsurprisingly another one of the CIA’s wacky schemes. It’s a program exploring the use of explosive bats was carried out during World War Two.

©Luuc Kieboom

They have previously tried to use explosive rats in World War One but to little effect. The attempts to weaponize bats in the Second World War met similar degrees of failure. According to the plans, a large canister would be dropped from a plane over Japanese cities. After that, a parachute would be deployed.

©United States Army Air Forces

The cannister would open, releasing hundreds of bats to settle in the Japanese buildings below. They equipped each bat with a small incendiary bomb on a timer. If all went according to plan, the bombs would set fire to the houses, causing widespread destruction. While the plan seemed promising at first, disaster struck in the testing phases. The bats destroyed an airbase after an error in their deployment. The costly damage contributed to the cancellation of the scheme.


They might not always have gone to plan, but it’s hard to deny the level of genius that went into some of these spy devices. We are getting better and better at spying on each other and carrying out covert operations. I wonder what crazy inventions intelligence agencies will come up with next? I just hope it doesn’t involve my hamster. Let me know what your favorite crazy spy devices are in the comment section down below. Thanks for reading.

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