The last minutes reveal that Split takes place in the same universe as M. Night Shyamalan’s superhero drama Unbreakable.
The film seems to pretty clearly set up a potential encounter in the future between Bruce Willis’ David Dunn and James McAvoy’s Kevin Wendell, aka, The Beast.
For those of you who have seen Split or have unfortunately already had it spoiled for you, you know that Split is, in its own way, a continuation of an existing franchise.