Mental health problems should never entertain. A movie that brings modern psychiatric work into disrepute

Rating: 1/10 (28 January 2019)

Wanted to watch the Movie as I just viewed "Glass" the other day, did not know it was a Triology.
First the movie itself: Multiple Personalities always sound fascinating - why not make a(nother) movie out of it. The Plot was quite clear within minutes into the film. It went on and on... like those teenager movies where they go camping in a haunted forest and one after another vanishes.
James McAvoy showed a superb performance with him changing personalities every other minute. He was the whole movie! He carried everything. The Girls and the Psychologists where forgettable.
Kidnapping movie, showing sexualized teenagers are stupid. Only Casey, who was abused herself, had some special abilities. And this must the real plot of the whole movie:
The ones who have suffered gain strength out it and develop some new powers. Casey staying calm and clever, Kevin becoming some super cross fit guy without training and knowing how. Mr. Dunn - nearly getting drowned by school bullying and now has visions what people are up to at the moment.
I don´t know if I can go with that... needing a Trauma to become especially powerful? Obviously here even getting criminal.
I work in psychiatric hospital for children on a closed ward .. and I am more then sure they would rather be normal, renounce the superpower and have not been traumatized???!
Anyway with movies like this, where someone with a mental illness(rare or not) does criminal things, brings modern psychiatric work into disrepute. In 2016 it should not entertain, it should educate that mental illness is as normal as breaking you leg and no one should be scared of them. I also urge the director, for gods sake, to even research those illnesses first and not bring in false information about DID. Shyamalan took a disease and invited it completely new, for dramatic reasons and in the end it just makes people with mental health problems look dangerous, evil and possibly criminal. Bad job!
Another plot whole that made me rage:
Cayses Story was shown with rape flashbacks all the movie along. How on earth could she stay calm through the whole film, being again in situation that might end up rape? Just at the end she showed some panic attack, which I believed her. I feel she, as a character, was really bad written.