Psycho-thriller with a twist, pls help me find it (spoilers)
In other subreddit someone found it, it's mindscape 2013
I saw this a while ago, so take the scenes with a grain of salt.
The start of the movie was with a girl, whose parents were killed, and she called 911 or someone I don't remember in a total panic.
A detective man moved in with her, in the house her parents were killed, tried to get closer to her to help her with the trauma, or to help the investigation with what she remembers.
The more they get closer (in a friendly way) the more the detective unveiled about her mental state and motives. There were drawings as well I think which were suspicious. She was very manipulative.
And the key (spoilers of the ending):
It turned out the girl was the killer, but by the time the detective found out, the girl escaped.
Later the detective got a cheeky letter from her.
I tried to get the answer from Gemini, but it was no help :(