Haven't not seen it's predecessors 'Unbreakable' and 'Split', I am blown away how good this movie was. It does summarize those movies (I believe) subtly throughout the film which caught me up to speed and not once did I feel like I missing key information. This sequel stands on its own - and that's a very good thing.
Following in the directors vision "The Incredibles, but a dystopian" it was more realistic and humanizing view of the superhero genre - very meta too, like 'Logan' where comic books of super heroes exist and serve an actual purpose.
Fantastic world building, though-provoking story and an ultimately real cool film from Shyamalan.