The movie Unbreakable was released in November 2000, when superhero movies were practically non-existent compared to recent years. It performed really well in the box office (making $95 million domestically). M. Night Shyamalan has had some great releases and obvious some weren’t received as well as others (Editor's Note: Ugh, don't get me started...) but he has stuck to his style of film-making throughout his career (minus Afterearth and The Last Airbender).
The Visit was a great bounce back movie for him.
Now with the release of Split…
*SPOILER WARNING AHEAD FOR SPLIT. I HIGHLY RECOMMEND YOU WATCH THE MOVIE IF YOU HAVEN’T YET.*
…Ok still with me? I really do highly recommend watching Split, but it is revealed at the end of the movie that it takes place in the same universe as Unbreakable, and even mentions Mr. Glass when discussing the films antagonist the Horde. I’m really excited to watch how Mr. Shyamalan takes on the battle between David (Bruce Willis) take on the Horde (James McAvoy).
Nerdbot will let you know whenever more concrete information becomes available.