When spies need to make sure their colleagues get a package or a signal without anyone else knowing, they leave a dead drop in a specific location and trust that another spy -- ideally the one they need to communicate with -- will retrieve the package. You don't have to be a spy to make use of dead drops though: they can be useful to safely leave a package for a friend, play a game with multiple friends, or leave yourself something you want to retrieve when the time is right.
Why Would I Ever Do This?
You've probably seen those scenes in spy movies where the hero walks up, sits on a bench next to someone else, says the secret passcode, and the stranger hands over an envelope or walks away, conveniently leaving their briefcase behind. This is a live drop, because both people were there at the same time and an item changed hands. A dead drop is the opposite -- one person leaves it without knowing if the other has -- or will ever -- pick it up. For that reason, dead drops need to be well hidden, but not so hidden that someone can't find it when it's needed. Photo by Jeremy Keith.
Granted, you may not need to do this on a regular basis, but leaving a dead drop can be useful in a number of ways:
- Geocaching is essentially the gamified hunt for dead drops, which can contain anything from prizes to secret messages to clues to find the next drop. Similarly, you can use dead drops to start your own scavenger hunt or game with friends for fun.
- Leaving a dead drop for a friend gives you a way to leave them an item on your schedule with the knowledge they will pick it up on theirs. Imagine leaving the keys to your house under the doormat, then making a small chalk mark on the door to signal to your dog-sitter that the keys are there. No mark, no keys.
- Leaving a dead drop for yourself will make sure you always have a cache of something where you might need it. For example, stashing an emergency get home bag in the storeroom at work where no one will find it (or even better, somewhere you pass on the way home every day) makes sure you will always be ready for an emergency.
How to Make Sure No One Finds Your Dead Drop
A dead drop found by the person it's intended for is valuable. To anyone else, it's either trash or a dangerous unattended package, so tread wisely here. Don't do anything stupid or dangerous, like leaving your drop outside an airport or police station. Even Geocachers have guidelines about where they are comfortable leaving caches so they don't get confiscated, destroyed or stolen. Photo by PK.
To that point, here are some tips to make sure your drop never gets found -- except by the person you want to find it:
- Make sure you agree on a "the drop is here" signal. If you're leaving a key for a spouse or pet sitter, for example, you want to make sure you give them a clue that the item they want is actually there. Aldrich Ames, a CIA agent convicted of spying for Russia in 1993, used chalk marks on mail boxes to signal to his handlers that he had left them something to pick up. Your signal could be a chalk mark, or even a sticky note in the corner of a window. Whatever signal you use, make sure you and the person picking up your drop know and agree on it, and that it's something that would never arouse suspicion from anyone else.
- Make sure your drop isn't so obvious that it attracts attention. The key example is a good one, but under the doormat? That's for amateurs. Want to leave your password for the IT admin who helps you out in your office? If it's in any of these places, you're doing it wrong. Instead, pick somewhere few people would look for that specific thing. That doesn't mean bury the key in the yard (although that's not a bad idea), but put it somewhere no one would look for a key, like in an empty soda can behind a bush next to the side door. Leave your emergency go-bag next to the coat rack in your office, where a bag wouldn't be out of place. The best dead drops are often in plain sight, but no one thinks they're noteworthy. Alternatively, you could go all out and hide your drop in a hollowed out book, behind a brick in the wall, or a even an inconspicuous can next to the garbage or on the side of the road.
- Consider how quickly your drop will be retrieved. If you need to leave a note for someone and you know they will be there to pick it up shortly after you leave it, consider putting it somewhere high-risk but quickly retrieved. Think scavenger hunt: I can leave a note with the clue to the next step of the hunt in a specific book at the library. If I know my contact will show up at 11am to pick up the drop, I can put the note in the book at 10:45 and walk away. My contact gets the drop and neither of us have to know the other's identity. Of course, the longer you wait, the more likely someone will check out your book!
- If you're leaving your drop for yourself, make sure it holds up to long-term storage. This goes for most drops, but make sure your drop will withstand the elements if it's outdoors. If you're leaving something for yourself, make sure it will be OK in its location until you need it. Real spies have used dead drop spikes -- metal tubes with screw-tops -- to store and preserve small items like USB keys, rolls of film or documents. If you're interested, they're not hard to make. Whatever container you use, it needs to fit in with the environment, and it needs to protect your drop.
As we mentioned above, the best drops are the ones that are in plain sight, or are only easy to find by someone who knows the signal and knows the hiding place. If you've ever been geocaching, the specific GPS coordinates of the cache and a few simple clues are used to lead you to the cache. Every cache I've found has been somewhere plain and public, where someone could find them if they knew where to look -- it's just that most people don't think to look under that park bench and open the Altoids tin taped to the underside, or think much of the plastic bag that's stuffed into a space between two brick buildings.
Geocachers leave and hunt dead drops for fun and thrills, but you can do the same to leave an item for someone. Just borrow a few tricks from the spy's playbook and you'll be a master at covertly, discreetly leaving packages for the right people to find.