WARNING: We’re sure you know how big a role the “twist ending” plays in any M. Night Shyamalan movie. Well, if you don’t want to be spoiled on the twist ending for the director’s new movie, Split, then stop reading now. Seriously, MAJOR SPOILERS revealing the twist lie ahead. Only read further if you’ve already seen Split… or if you genuinely don’t care about having the movie’s ending ruined for you.

I’m not kidding. This is your last chance to look away.

You sure?

Well, okay then.

The one thing audiences going into Split probably already know is that it focuses on a dangerous man with a multiple personality disorder, played by James McAvoy, and the three girls he kidnaps. What you won’t know until you’ve seen the film is that McAvoy’s character has the supernatural ability to summon all his personalities at once and become an invulnerable monster with animalistic tendencies. An even bigger reveal: this supervillain, if you will, inhabits the world of Unbreakable, as we learn when Bruce Willis’ David Dunn shows up at the end. Yes, like 10 Cloverfield Lane and Blair Witch, it’s a stealth sequel/spin-off you never saw coming. Until now.

“This was a character that was in the original screenplay [for Unbreakable],” Shyamalan told a packed house at AFI Fest back in November 2016. “I pulled him out. He was throwing off the balance of the piece [by being] too many characters.” When he wrote this character, who goes by the name of “Kevin” (among many others), Shyamalan says he found himself just wanting to spend time with all the personalities. Faced with a lower budget and an actor who was up to the challenge, the director relished the chance to do, essentially, a one-shot spin-off.

“I’m an eternal optimist,” Shyamalan said. “Even today, I’m an optimist!” He’s fascinated by psychology, and saw in Kevin a way to turn a mental disorder on its head by giving him strengths rather than weaknesses. He was inspired to cast McAvoy when they met briefly at Comic-Con. Though the original plan was for Kevin to use makeup and wigs to hide behind for his various guises, the sight of the actor with a buzzed head for his Professor X role reshaped the character. Shyamalan reinvented him as one who does not hide behind costumes and props, but throws himself into the multiple roles. McAvoy was quick to note that he did not get paid 24 salaries, but says of his director, “He did complain about how much my lawyer tried to get me.”

Discussing McAvoy’s many onscreen personalities, both McAvoy and costar Anya Taylor-Joy said that their favorite was Hedwig, a nine year-old boy who was the hardest to nail in rehearsals but the easiest to play onscreen. “It’s so easy to make it over-the-top,” said McAvoy, joking that the audience will probably say he did that anyway. The key, as he articulated, was to remember that the character not a dumb man, but a smart boy.

In one particularly memorable scene, Hedwig invites Taylor-Joy’s Casey to his room to watch him dance, and he proceeds to engage in what looks like a terrifying freakout directly into the camera. You’ll know the scene when you see it, but you might not know quite what is going on. It seems that McAvoy, in his own mind, was enacting a story of zombie attack: freaking out with fear, getting bitten, and then turning.

Asked for his take on the movie by moderator Grae Drake, producer Jason Blum smiled and said, “I was very happy with the thing that they did.” A more emotional Shyamalan insisted that this risky movie, one involving cannibalism and molestation, could not have been made without Blum. To that, Blum defended the filmmaker, who says he still feels insecure about everything he makes. “If we feel safe, I’m not sure what we’re doing,” he said. On a low budget, however, he had time for plenty of reshoots, scheduling three extra days after three weeks of editing revealed what else he needed.

To close out the night with some amusing trivia, the M. Night revealed that Split‘s Betty Buckley—who had played the crazy lady in The Happening—was up for a lead role in The Visit, but balked at doing nudity. While Buckley says she was very impressed with that movie in the end, she was relieved not to have taken on the full-frontal role.

Everyone remained mum on the prospect of a full-on Unbreakable sequel, but perhaps they’re waiting to see how Split does first.

Are you pumped at the prospect of more David Dunn and Mr. Glass on the big screen? Does this mean most Shyamalan movies, like Tarantino films, happen in the same universe? Give us some Signs in comments below.

Images: Universal

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