The Ending (spoilers)
This movie had two parts that made it go from generic to good/great in my opinion.
They did not take the easy way out with the ending. In fact they spent the whole run of the movie successfully building up my second favorite part, their unique and deep friendship so that when the climax was happening I felt true suspense and hope for both characters. "Frailty (2001)" was great, but way too many movies use the trope of the lone crazy person being dun dun dun The only sane one! This movie on the other hand played the whole reveal out in a way that really made me excited and happy.
All of the actors were great. And with such a small cast and so much tension to be built relying on their performance without an over abundance of special effects or silly jump scares. The low use of fx made the one occasion all the more creepy and to see the incomparably sweet marra slowly shift into a leering terror stuck with me. They cast her perfect for it.
When I had come across this title and read the description I wasn't sure if I should e othered to watch it, so glad I did.