This month marks the return of M. Night Shyamalan as he finishes the trilogy that started with Unbreakable in 2000 and continued the story with Split 17 years later. Fans didn't have to wait as long this time, as the response to the reveal that the two movies were connected proved to the studio that finishing the trilogy was a priority.

Related: Samuel L Jackson Explains The Extraordinary In New Glass Clip

However, before Glass hits on January 18, it might be a good idea to get a refresher on what happened in both previous movies, as well as who the three main characters really are. If you don't have time to rewatch the first two movies, here is a look at 10 important plot points from Unbreakable and Split to remember for the sequel, Glass.

10. HOW DAVID DUNN GOT HIS POWERS

Bruce Willis in Unbreakable

In Unbreakable, David Dunn (Bruce Willis) was a security guard in Philadelphia who was going through some problems at home. His marriage was falling apart and it was affecting his son Joseph. However, one day David was riding on a train -- coming home from a job interview -- when the train derailed and crashed. Everyone on the train perished except for Dunn, who walked away without an injury.

He meets a mysterious man named Elijah Price who tells him that he has incredible powers and said the proof is in the fact that David had never suffered a serious injury in his life. David starts to test himself, taking his body to the limit and learns that was Elijah was saying might be true.

9. WHO IS MR. GLASS?

Glass: 10 Important Plot Points From Unbreakable and Split To Remember For The Sequel

The man known as Glass in the new movie is Elijah Price (Samuel L. Jackson). The self-proclaimed supervillain of the Unbreakable movie world, Price is known as Glass since he was born with Type I Osteogenesis imperfecta. This means that the collagen produced by his body is insufficient to protect him from injuries.

His bones are fragile and break easily and he spent most of his life injured or recovering from serious injuries. When it comes to his status in life, Elijah believes that if he is so fragile and glass-like, there had to be someone out there who was his polar opposite -- someone like David Dunn.

RELATED: M. Night Shyamalan & Sam L. Jackson Defend 'Unbreakable', Talk Sequel

8. WHAT ARE DAVID'S POWERS?

Bruce Willis in Unbreakable

David Dunn escaped the train crash without an injury. As Elijah pointed out to him, he had never suffered a serious injury in his life. He was, in fact, the antithesis to Elijah's weakened glass-like condition. Throughout the running time of Unbreakable, Dunn tested his body. He even bench pressed 350 pounds -- which was more than he could do before the accident.

However, Dunn's most important power is that of extrasensory perception. David learned that when he touched other people, he could see things that they had done in their past -- including criminal acts. He used this to stop a psychopath and save some lives. He became a superhero -- at least for a time.

7. WHAT WAS THE PLOT OF UNBREAKABLE?

Glass: 10 Important Plot Points From Unbreakable and Split To Remember For The Sequel

When it comes to the basic plot of Unbreakable, David Dunn went through a typical superhero origin story. However, this was nothing like the capes and tights superhero origin stories of Spider-ManIron Man or Captain America. In this case, it was just David -- an everyman -- who learned he had powers and tried to figure out how that affected his life.

His son Joseph was excited at the prospects of his dad having incredible powers, and that meant more to David than fighting crime. It wasn't until he saw a vision of a wife and children in danger and went to save them that he became a hero. He took the life of the man holding them captive, but that was the extent of any superhero action in that brilliant film.

RELATED: M. Night Shyamalan May Become Unbreakable Again

6. THE M. NIGHT SHYAMALAN UNBREAKABLE TWIST

Glass: 10 Important Plot Points From Unbreakable and Split To Remember For The Sequel

While Unbreakable was a great movie based on just the basic plot of David Dunn's self-discovery, this was an early M. Night Shyamalan movie and therefore had a twist. However, unlike some of his more ridiculed twist endings, the ending of Unbreakable brought an entirely new level to the movie.

As fans who watched the Glass trailers know, Elijah is the bad guy. That was always the case. It turned out that Elijah was the man who orchestrated numerous disasters that took the lives of hundreds of people. He was looking for someone to walk away from an accident unscathed because he wanted to find his polar opposite and finally give the comic book obsessed psychopath a true nemesis.

RELATED: 9 Reasons M. Night Shyamalan Is a Great Filmmaker

5. WHO IS KEVIN?

James McAvoy in Split

Kevin Wendell Crumb (James McAvoy) is a man suffering from dissociative identity disorder. In Split, he was seeing a psychiatrist (Betty Buckley), who believed she was helping him keep control of his life despite 23 personalities fighting for control. What she didn't know was that he had already submitted himself to two of the more dominant personalities.

As a result, Kevin became a predator. In Split, he proved to be a sociopath who kidnapped young girls and prepared them for a horrifying fate. That fate involved what was revealed to be a 24th personality -- the most dangerous one of them all.

4. WHAT ARE KEVIN'S SPLIT PERSONALITIES?

Glass: 10 Important Plot Points From Unbreakable and Split To Remember For The Sequel

There are a number of interesting personalities that Kevin showed off in Split. The original dominant personality was that of Barry, a sensitive artistic personality -- or at least it was for a long time while Kevin was seeking psychiatric help. Barry would allow other personalities some time to speak but often held down two other personalities due to their dangerous traits.

Those personalities included Dennis, someone who liked underaged girls, and Patricia, someone who was very mean and dominating. That was smart because when those two came to the forefront, they took over Kevin's body from Barry and helped bring out the 24th personality -- The Beast.

RELATED: Jason Blum Calls Glass a 'Very Different' Superhero Movie

3. THE CASEY KIDNAPPING

Glass: 10 Important Plot Points From Unbreakable and Split To Remember For The Sequel

The plot of Split involves Kevin kidnapping three girls at a shopping center and then locking them away in underground tunnels that rested under the zoo where he had worked. His entire reasoning for this was to prepare them for the arrival of The Beast -- the 24th personality that both Patricia and Dennis worshipped.

While held captive, Casey, Claire, and Marcia met a number of the personalities, including the child-like Hedwig -- someone that Casey befriended and asked to help her. However, Dennis and Patricia were too strong. Casey finally escaped after her friends perished and Kevin gave chase as The Beast arrived.

RELATED: Glass Script Is Making Cast Elevate Their Performances

2. THE BEAST

Glass: 10 Important Plot Points From Unbreakable and Split To Remember For The Sequel

It turned out that The Beast was not just a myth but it was indeed a hidden personality that was lurking in Kevin. This was a mixture of many of the animals that Kevin used to watch at the zoo where he worked and somehow, without much in the way of explaining the reasoning, Kevin developed powers. This included superhuman strength, the ability to crawl across the walls and more, making him the ultimate predator.

Unlike Glass, Split was a horror movie about three girls trying to survive an experience with a monster. Glass will take on the superhero genre and have Kevin as a monster with no apparent weaknesses battling a good man in David Dunn, who might be his equal and the perfect superhero to battle this deranged villain.

1. THE M. NIGHT SHYAMALAN SPLIT TWIST

Glass: 10 Important Plot Points From Unbreakable and Split To Remember For The Sequel

The question remains. How did Split become the sequel to Unbreakable? There was nothing in the advertising that indicated that the two movies were connected at all. As a matter of fact, M. Night Shyamalan had denied Unbreakable 2 for years. But, as with his entire filmography, it was all in an attempt to deliver yet another brilliant twist at the end of the movie.

In this case, it wasn't even apparent. Kevin chased Casey through the tunnels, but she escaped. Kevin also escaped. While Casey was taken home by the authorities, Kevin was shown realizing what he had become. Then, in a post-credit scene, a small diner showed the events on the TV news and a woman compared it to someone called Glass. That is when David Dunn was shown watching the TV and the sequel reveal was delivered.

Next: Screen Rant's 50 Most Anticipated Movies Of 2019

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