Finding a coin wedged into your car’s passenger-side door handle can be confusing—and understandably unsettling. Stories about this supposed “penny trick” have circulated online for years, claiming that thieves use a coin to prevent a car door from locking. While the theory is often exaggerated, discovering something unusual on your vehicle is still a good reason to stay alert.

According to the viral story, a thief places a penny or nickel beneath the exterior door handle, supposedly interfering with the locking mechanism. The driver then presses the key-fob lock button and walks away, unaware that one door may have remained unlocked. On most modern vehicles, however, this trick is unlikely to work as described, because electronic central-locking systems generally operate separately from the exterior door handle. Some vehicles will also warn you if a door hasn’t locked properly.

That doesn’t mean a coin should simply be ignored. It could be a prank, a coincidence, or an attempt to distract you. Someone could take advantage of the moment while you’re focused on removing the coin, especially in a busy parking lot. In some situations, unusual markings or objects around a vehicle may also be intended to draw attention to it, although there is no reason to assume that every coin found on a door handle is connected to criminal activity.

If you discover a coin or another strange object attached to your car, don’t linger in an isolated area while investigating it. Get inside, lock the doors, and move to a safe, well-lit location before taking a closer look. Once you’re somewhere secure, check that all doors are properly locked and consider notifying parking-lot or building security if the vehicle appears to have been tampered with. The viral “penny lock trick” may be largely a myth for modern vehicles, but staying aware of your surroundings is always the smarter response.