The title was changed to "The Watched" in the UK and Ireland to avoid confusion with the Netflix series The Watcher (2022).
Mina and her sister Lucy were named after the best friends from Bram Stoker's Dracula.
At approximately 15 minutes in, when Mina's car breaks down in the forest, the size of Darwin the bird increases.
In a 2024 interview on the Roger Ebert website, Ishana Shyamalan spoke about her shooting strategy for the film: "I had this one director friend on Servant (2019) who gave me some amazing advice. He said, 'If you can't see the scene play out in your head while you're writing the script, it's not right. There's something wrong with it.' I heeded that thought intensely when going into shooting, I needed to see every shot beforehand. I'm the type of director where I know the cut points for my shots. I was trying to play a bit, though. There were so many graphic angles, and with my crew, we were trying to find the most uncomfortable way we could frame something, which often meant more headroom, more negative space in a frame, and shooting through things ... we wanted that feeling of discomfort in every frame where nothing is exactly what you want to see or hear. Things are either too close, or they're too far.
We also used these vintage rehoused lenses, which give the whole film this weird vignette and this expansive feel."