Elijah Price a.k.a Mr Glass is the main antagonist of Unbreakable. At once David Dunn's mentor and archenemy, he is also the owner of "Limited Edition" shop and (as the finale reveals) a supervillain.
He is portrayed by Samuel L Jackson.
Elijah Price was born with Type I Osteogenesis Imperfecta, a rare genetic disorder which left his bones extremely brittle: merely being born was enough to break baby Elijah's limbs, as the attending physician quickly discovered. Young Elijah was relentlessly mocked throughout his childhood by the other children in the neighborhood, who often called him "Mr Glass" for his frailty; for good measure, constant visits to the hospital ensured that he remained isolated throughout his childhood, forcing him to seek solace in his one major hobby - reading comic books. However, as deleted scenes reveal, he continued his attempts to try and fit in, often with disastrous consequences: at a visit to a fairground, he attempted to ride one of the rougher rides - only to end up breaking several bones after his improvised safety padding slipped out of the ride.
Eventually, the bullying and potential for further injury got too much for Elijah, and he resolved to never leave the house again. However, his mother came up with a solution: buying a large supply of comics as presents for her son, she would regularly put one of them on a park bench just outside their house, essentially forcing Elijah to go outside to retrieve the comic before it could be stolen by a passer-by. Though this gradually had the effect of boosting his confidence and encouraging him to go outside, he never achieved much of a social life, and Elijah spent much of his time alone.
As he grew older, Elijah began to ponder the existence of a superhuman: drawing on his extensive knowledge of comic books, he came to believe that superheroes had once been a reality in history, that people with "real" superpowers had been lionized in history as mythical heroes and eventually exaggerated beyond reality by the modern entertainment industry. He even theorized that, if he represented the frailest a human being could be, perhaps there might be someone in the world who stood at the opposite end of the scale - someone who couldn't be injured like most humans. This was to form a lifelong obsession, beginning simply with him studying the newspapers for stories of people who'd survived catastrophic disasters without being harmed; however, this gradually grew to dangerous extremes.
As an adult, Elijah's devotion to comic books gradually inspired him to start his own comic book art gallery, Limited Edition; though regarded as a perfectly respectable business by the general public, it was also to become Elijah's workshop - his office becoming a planning center for continued attempts to locate his superhuman antithesis. Here, he would make bombs, plan future acts of sabotage, and chart the patterns of survival in catastrophes throughout the world - some of them planned by him, some entirely accidental.
Just prior to the events of the film, Elijah had begun his search for his opposite in earnest by bombing an airplane and burning a hotel to the ground, both incidents resulting in hundreds of casualties. Disappointed by the absence of survivors, he continued...
The film begins with Elijah orchestrating a train crash, killing a hundred and thirty passengers and crew. However, this time there was a survivor: David Dunn, a humble security guard. Seeking him out, Elijah plants a business card on the front of David's car, inviting him to Limited Edition; however, after hearing the eccentric art dealer's theory, David isn't convinced and leaves under the impression that he's being scammed.
Undeterred, Elijah follows him to the football stadium where he works, gradually charming him into an extended conversation. However, while walking past a queue of people waiting to be allowed into the stadium, David reveals an instinctive power to sense criminal behavior or past wrongdoings by touch, intuiting that one of the men in line is carrying a gun. Though Elijah considers this further proof of superhuman powers, David is once again dismissive. However, Elijah decides to follow the man out of the stadium, but trips while descending a flight of stairs and shatters several bones - though he is vindicated when he discovers that his quarry is indeed armed.
Now wheelchair-bound for the next few weeks, Elijah is assigned to physiotherapy and, as luck would have it, his therapist is David's wife, Audrey. Over the course of their time together, he learns that David supposedly injured himself in a car accident, ending his football career; however, Elijah believes that David faked his injuries and abandoned his future in sports in favor of his marriage to Audrey - a theory eventually proved true. David continues to disbelieve Elijah's theories of superhuman resilience, citing an incident in which he almost drowned, and considers ending their discussions after his son almost shoots him in an attempt to prove his powers exist. However, Elijah eventually convinces him that this vulnerability to water is merely a superhuman Achilles Heel, and encourages him to use his powers to seek out wrongdoers.
After doing so - managing to rescue two children from a murderous home-invader in the process - David attends an exhibition at Limited Edition to celebrate: here, Elijah congratulates him on finally discovering his true purpose in life, and shakes his hand. However, David's power to sense wrongdoing reveals Elijah's crimes to him - including the train crash - and he can only stare in horror and disbelief as his mentor reveals himself, claiming that the deaths were all justified as a means to find a true superhero.
Overwhelmed with emotion, Elijah explains that he finally knows his purpose in life - to be the arch-villain to David's hero, even going so far as to suggest that his childhood moniker, "Mr. Glass," should have alerted him to the fact that he was always a meant to be a villain. Unable to bear the truth, David leaves. The final captions reveal that David led police to Elijah, who was committed to an institution for the criminally insane. Despite his imprisonment, Elijah was satisfied that he finally achieved his goal in finding a superhero and justifying his own existence as a supervillain.