June 15th, 2015

Writing Spies: Finding Bugs – Who, When, and How?

Bayard & Holmes
~ Jay Holmes

In our last Writing Spies article, we talked about bugging rooms.* But what if our characters need to know if a room is already bugged?


These guys expect to be watched. Bugging them could be difficult.

These guys expect to be watched.
Bugging them could be difficult.


First, consider the character being bugged and the character or organization doing the bugging.

Some characters are going to expect surveillance. For example, Mafiosos and the FBI agents that hunt them are going to be constantly suspicious that they are under surveillance. Successfully bugging them will require a higher level of technical skill and caution than what would be needed to bug characters who don’t have reason to suspect they are being watched.

On the other side of the equation, a jealous spouse or neighborhood pervert is not likely to be as skillful at placing bugs as an FBI Agent, CIA employee, or even your local police.


These people don't expect to be watched. Bugging them won't be difficult.

These people don’t expect to be watched.
Bugging them won’t be difficult.


Next, consider when and how the bugging equipment was placed, and precisely when the target would become suspicious.

If the target is a business executive or CIA employee visiting China, Russia, or another police state, he would assume that he has been targeted for surveillance, and he would sweep his hotel room or rental car routinely. He would also assume that he could be targeted by mobile bugging equipment when he leaves his hotel.

Does it seem odd to you when a surveillance target such as a mafia goon suspects a bug and proceeds to have a loud conversation about it with his co-goons in the room? An intelligent person does not announce suspicions.

Remaining calm can give the surveillance target an opportunity to discover a suspected bug without the surveillance team being alerted. The target can then use the bug to misinform his opponents and send them on wild goose chases.


Wired/Wireless Camera Detector from Brickhouse Security

Wired/Wireless Camera Detector from Brickhouse Security


Once you’ve considered the players, it’s time to think about the technology.

Bug sweeping devices with various levels of sophistication are readily available to the public at costs ranging from $25 for a simple sweeper to $1,500 for a decent sweeper with full spectrum analysis capabilities. (Google “bug sweeping devices retail.”) So even in the case of a non-professional or non-criminal, a character can readily obtain electronic sweeping equipment.

In the age of tiny video cameras and transmitters, we all have to assume that we are under video and audio surveillance.

This means that characters need to sweep the room or building without being obvious. Modern sweepers can be disguised as working cell phones, which can generate vibrations rather than tones. A character can hide her true aim of detecting surveillance equipment by placing a fake call on the device and pacing the room while conversing.


She seems to be picking up something. Image from Canstock Photo.

She seems to be picking up something.
Image from Canstock Photo.


Sweepers detect transmissions from either microphones or cameras, and they do not distinguish between the two. If your character doesn’t care about tipping off the surveillance team, he can use the sweeper to zero in on the transmission and then inspect the vent, lamp, furniture, etc. to discover the nature of the transmitting bug.

More sophisticated bugs can be remotely controlled to limit transmissions, but more sophisticated scanners can detect them even when they are not transmitting.

A sophisticated target might wait until nighttime and use infrared detection to find heat being generated by bugs.

This method is quite effective for most bugs. If a character waits a few minutes after turning off the lights to let the walls and furniture begin to cool down, she can find nearly any bug with the right sensing equipment.

Smoke detectors and refrigerators can mask a bug’s infrared signature, so they need to be inspected visually.

One technique for bug detection involves searching for pinhole camera surveillance.

Pinhole cameras rely on small amounts of light coming through a wall via multiple pinholes. A character would turn off the lights and then, while looking through an empty toilet paper tube, wrapping paper tube, mailing tube, etc., he would sweep the walls with a bright flashlight and watch for inexplicable small reflections. Such out-of-place light sources may indicate a pinhole camera system.


Canstock 2015 June Bugs man staring through TP tube

Another type of bugging a writer might employ in a story is an infrared laser system that bounces off windows.

A character can monitor the laser’s reflection, and the glass’s vibration can be measured and interpreted as sound. Basic infrared sensing equipment can detect these systems and pick up conversations from a targeted room without having equipment inside.

In the absence of bug detection equipment, a character can be clever and use his regular cell phone to do a basic bug sweep, even if it really is just a cell phone.

By placing a call and then pacing the room, she can locate radio noise sources. Electronic noise might indicate a bug, but it might also indicate what you already suspected – that we all pay far too much for hideously low quality cell phones. Higher quality bugs will not be detected by a regular cell phone.

The equipment and techniques are fun to consider, but before considering the technical aspects, be sure to consider the situation and the characters. Remember, whether the character is a complete innocent or a cunning old spook, the most important debugging tool is his brain.

Do you have spy questions? Bayard and Holmes will be checking in…

Related Writing Spies Articles:

Which Intelligence Agency Does What to Who?

How the Pros Bug

Truths of Spycraft You Don’t See in Fiction

* * * * * * * * * * * * *

Bayard & Holmes Official Photo

Piper Bayard, is an author and a recovering attorney. Her writing partner, Jay Holmes, is an anonymous senior member of the intelligence community and a field veteran from the Cold War through the current Global War on Terror. Together, they are the bestselling authors of the international spy thriller, THE SPY BRIDE, to be re-released in spring of 2015.

THE SPY BRIDE Final Cover 3 inch

Keep in touch through updates at Bayard & Holmes Covert Briefing.

You can contact Bayard & Holmes in comments below, at their site, Bayard & Holmes, on Twitter at @piperbayard, on Facebook at Bayard & Holmes, or at their email, BH@BayardandHolmes.com.

11 comments to Writing Spies: Finding Bugs – Who, When, and How?

  • I’ve always been curious about how small the cameras actually are. Are we talking a watch battery? And why are you always reading about people bugging picture frames?

    • I think with the picture frame, someone did it in fiction a long time ago, then someone else did it, and so on, and now it’s kind of accepted as fact. As far as how small cameras actually are, I do not know, and Holmes cannot legally answer that question. Let’s just say if they are the size of a watch battery, you’re well within the realm of possibilities.

      Thanks so much for having us here today. 🙂

  • Stuff like this freaks me out! Then I see on the news where some perv is putting a camera in the changing room of a department store. I have to admit, I think about that every time I go in one!

    But hell, he’s gonna get more than he bargained for with this chick! 😉

  • Piper, I totally love this article. Got my creative juices flowing. One of these days I want to write a spy/caper novel. You are my “go to”source for all things spyish. Thank you so much!

  • Fae Rowen

    The infrared/heat detection is cool. But checking the smoke detector would be a pain every time you re-enter the room. The frig–no problem checking that! Though, I guess a sound only bug could be behind the frig.

    We all know about traffic cams, security cams, etc. that help solve crimes. Realistically, how worried does a non-cheating, drab spouse need to be about bugs in hotel vacation rooms, rental car tracking, etc?

    Laura, what freaks me out more is cyber-spying!

    • Hi, Fae. Realistically, the average, non-cheating spouse does have more reason to be concerned about cyber-spying. Criminals are endlessly creative, and identity theft is on the rise. There are all kinds of people with nefarious motives who can steal information and watch or listen to us through our phone/iPad/computer cameras and speakers without any indication to us that it is happening. Even the Pentagon and the Office of Personnel Management could not keep from being hacked. I keep post-it stickies over my computer camera at all times, and pay attention to the angles that my phone camera can see.

  • Thanks for the great information! Wish I was being bugged so I could do a sweep of my house. I bet hubby wouldn’t let me buy the infra red even for ‘research’ 🙂

    • Tell hubby that it will help catch squirrels that steal from your bird feeders, or better yet, that it will help keep track of where all of those kids are. 🙂