The movie itself is told from the perspective of amateurs who don’t know much about possession and the spirits that they are talking to. However, the Philippou brothers carefully developed the supernatural world of their film in what Danny dubbed a “mythology bible.”
“It was all in that mythology bible where we broke down every single spirit that’s connecting, why they’re acting a certain way, what emotions they’re connecting to, and how that spirit died,” Danny revealed to Slant Magazine.
This will probably be expanded upon in the prequel film, which has already been shot. However, they don’t want to spoon feed this well of knowledge to the viewers and prefer to drop hints for attentive viewers.
“We tell you a little bit about how the spirits died even with the sound design and all that sort of stuff,” Danny continued. “Part of me really wants to publish [the mythology] and say, ‘Look! Look at all this work we did for the thing!’ But the other part of me is excited about planting the seeds and having people find [out]. There are scenes I know that people rewatching it will be able to figure out.”
If a rewatch doesn’t give you the answers you’re looking for, you’ll just have to wait for the prequel to learn more. Hopefully, we won’t have to wait for too long!