I have to admit that I do really enjoy this movie. And have re-watched it many times, and showed to whoever I manage to watch a movie with.
Unfortunately, I have to address one big issue with it as well.
This movie, or rather M.Night Shyamalan, made one giant mistake in regards to using D.I.D. as a way for his character to have a "super power" and to be a complex villain.
The odd thing is, this movie does get a few things right.
It does, bear with me.
First, it is accurate that D.I.D. is developed via experiencing severe, complex, often repeated trauma as a child any time from 0-8 years old.
For those who don't know. Basically, when a child (between these ages) is put through enough trauma (all types, too many to list), that is too much for them to handle and live every day life, as most of these children have to do. Their brain goes, "I am not going to survive this, if all the parts of me know it's happening". So, the child dissociates HEAVILY and the brain separates itself to save itself.
The second bit that he got right, is that the alters can be as different as me to my neighbours, or you to your least favourite coworker for example. The alters aren't always totally different from one another, but in a lot of cases they are.
Third, I would give him credit for the character having a therapist, though she does go pretty heavy into the supernatural side of D.I.D., which there isn't necessarily unless you look at it that way. But he has one, and I will actually give him credit for the detail of the teenage girl prank that may have set the "dangerous alters" into motion. Which, I will get into in a moment.
Lastly, I will also give Shyamalan the credit of getting the first word of the Disorder right. Meaning, he does indeed show the Dissociation accurately. The alters do not know what's been going unless they are co-conscious, and he shows them fronting, clearly just waking up more or less.
Unfortunately, the entire plot of the movie was a bad idea. Because here's the TRUTH. You would have a better chance of winning the lottery than finding a person with D.I.D. who has a dangerous alter. I honestly don't know if anyone out there right now, has D.I.D. and a dangerous alter.
There is no such thing as a "beast with abilities" in alters. Or maybe in their inner world they do, but not in the physical world we reside in. People with D.I.D. are not dangerous and are not monsters. They are human beings who have been through hell, and saved themselves because no one else would. THESE ARE PEOPLE WHO WERE TRAUMATIZED TO THE POINT OF POTENTIAL DEATH, likely by or through a primary caregiver, and no one was there for them. No one rescued them, no one did anything about it.
So they saved themselves, and their brains were broken into pieces as a result. They are scared people who just want to be believed and understood.
Part of that was anger toward recent YouTube events, not anyone reading this. Which, if you have, thank you so much!
And, if you'd like to know more about the disorder, please watch one of the MANY videos that are educational on what D.I.D. is. I would recommend Dissociadid as they are very educational and the system that hosts the channel deals with D.I.D. on a daily basis. Or Anthony Padilla's "Day with Multiple Personalities" video. Which isn't really titled correctly, but that's not important here.
(SPOILER AHEAD, last sentences)
So, Split, made one huge mistake. But, while it does not represent actual D.I.D., it does get details accurate and honestly it's worth a watch. I say this because James McAvoy does do a very good job at acting in this movie. I'll also give a special shout out to Anya Taylor-Joy because she did (in my opinion) a very good job in her role of a teen girl who is abused by her Uncle. and I do actually love how that ends up saving her in the end.
So, in conclusion, this movie is worth a watch but please keep in mind that it is NOT an accurate representation of someone with D.I.D. It is simply a good movie with some excellent acting, a definite darker theme as the synopsis would suggest, but I would agree that is is one of Shyamalan's better movies.