Hideo Kojima’s PT is a delisted playable teaser for a long-canceled game that has become an infamous horror staple in the five years since it released. It’s a tense, first-person experience that sees players walking through the same looping hallway while ghostly sounds and shadows give them the impression that they’re not in that home alone.

Turns out, at least some of that tension was achieved by actually tethering the model of PT’s starring specter Lisa directly behind the player character early on in the game. Doing so causes Lisa’s shadow to sometimes be caught on a nearby wall, though players are never actually able to see the in-game ghost following behind them for the duration of the game.

Prolific game hacker Lance McDonald discovered as much after reworking how the typically first-person camera behaves in-game, allowing him to keep the camera stationary while the protagonist continues to move around the map. While he has plans to dive deeper into the game and post a video of his findings, he shared this early discovery in a quick thread on Twitter, along with a video of the ploy in action.

Unfortunately, without actual insight from the dev team, it’s not possible to nail down exactly why this very literal approach was taken versus other routes the Kojima Productions team had to set up those subtle audio and visual scares, but this latest discovery offers an unnerving look into how some of that atmosphere was created.

While there are moments of the game where Lisa comes into full view, those encounters are quite different from what McDonald’s video offers, meaning this newfound trick likely largely served as a hidden way to add to the game’s already creepy ambiance.