Split was an unqualified hit and most of the credit for that goes to James McAvoy. In the role of Kevin Wendell Crumb, he played a man suffering from dissociative identity disorder who contained a total of 24 distinct personalities inside him. McAvoy then had to play each one as its own separate character, creating an entire cast from a single actor.
With Glass on the way, we know we're going to get to know many more of Kevin Wendell Crumb's personalities, but the ones we've already met are sure to make a major impact. Here's a quick rundown of everybody we've already met and the role they play in Kevin's life.
Barry is a key personality inside Kevin, as he was originally the dominant personality (when we see a list of the personalities later in the movie, Barry is number one). His singular focus is the protection of Kevin, which frequently includes attempting to keep the other personalities in line so that they don't end up hurting him. Barry probably qualifies as the most "normal" of Kevin's personalities. He has a passion for fashion design, frequently showing his creations to psychiatrist Dr. Fletcher. Eventually Barry loses his dominant position to two other personalities, Dennis and Patricia.
With Kevin clearly in danger in Glass, Barry could be key to whatever resolution the film provides. If Barry is able to reestablish dominance, he could change the complexion of any situation involving Kevin very quickly.
Dennis is one of Kevin's most dangerous personalities. He tends toward violence and his sexual tendencies put the kidnapped girls of Split in constant danger. Dennis is the personality guilty of grabbing the girls in the first place. He also attempts to impersonate Barry with the psychiatrist in order to divert any suspicion of what he and the others are up to.
Dennis suffers from some degree of obsessive-compulsive disorder and is obsessed with cleanliness. While he may be a dangerous personality to other people, he also acts as a caretaker for the other personalities, so he's not entirely heartless.
Patricia is sophisticated, proper and orderly. She's one of the few, but not only, female personalities inside Kevin, and she, along with Dennis, takes a lead role in controlling the group throughout most of Split. For all intents and purposes, she's the mother of the group. She comes across mostly as polite, offering you a sandwich if you'd like one. But if you disobey her, she can be as vicious any other voice in Kevin's head.
This was without question one of the better performances that James McAvoy created in Split. Patricia is a cold and calculating sort of evil, and she wants nothing more than to bring forth The Beast. Since she was ultimately successful, it will be more than a little interesting to see what she does next.
Hedwig is one of the personalities that gets a lot of time "in the light." He's nine years old and most of the rest of the personalities inside Kevin tend to act like his parents. They tell him what to do and he does his best to carry out their orders, though, being nine, he often fails to get things just right. He's the only personality that tries to befriend any of the captive girls in Split, largely because he has a crush on them.
We see a lot of Hedwig in Split, so it's a safe bet that will continue in Glass. Although, it will be interesting to see how a child reacts to being locked away in an asylum.
Jade is one personality that we only see a couple of brief times in Split. She appears briefly in a video file that Casey finds on Kevin's computer. There we learn that she is diabetic, a medical oddity since none of Kevin's other personalities are. She appears to be a teen or a young adult, though her exact age isn't clear.
She pops up again briefly after Kevin begins to retreat from reality. She clearly wants to protect him, though her exact allegiances in regards to The Beast are not clear.
Orwell is another personality that we only get brief glimpses of. Like Jade he shows up in a video file and then briefly speaks to Casey after Kevin begins to lose control. He's well educated, particularly about world history.
The only other thing that we know about him is that he is one of the personalities that is against The Beast coming out, which could potentially make him an ally to David Dunn in Glass.
Throughout the entirety of Split, there is some question as to whether Kevin's 24th personality actually exists or not. Those that believe in The Beast spend the film waiting for him to emerge, seemingly without any real evidence that he will. However, in the end, The Beast does arrive.
Kevin's body physically transforms to become more muscular and The Beast is capable of seemingly superhuman feats, including being able to scale sheer walls. The Beast is violence personified and his freedom at the end of Split means that terrible things are likely to happen.
Kevin Wendell Crumb
Kevin is technically the base personality of the character played by James McAvoy. Abused by his mother, Kevin retreated from reality and created these many other personalities to help protect him from her. By saying his name, Casey is able to bring Kevin into the light, though it's clear that's a place he has no wish to be.
It seems likely we'll see Kevin again in Glass, if anybody is able to get him to emerge once again.
From Kevin's computer files, we do know the names of every other personality inside Kevin Wendell Crumb. They are: Heinrich, Mary Reynolds, Norma, Goddard, Bernice, Polly, Luke, Rakel, Felicia, Ansel, Jelin, Kat, B.T, Samuel, Ian and Mr. Pritchard. However, we do not actually meet any of them during Split. Since James McAvoy apparently plays 20 different characters in Glass, it does seem we'll meet several of the other personalities very soon.
We'll meet these other personalities and reunite with a few when Glass opens in theaters tomorrow, January 18.