For "Glass", M. Night Shyamalan has converged the world of "Split" (a story about a man, essayed by McAvoy, with over 20 different personalities who kidnaps three teenage girls) and "Unbreakable" (about David Dunn, essayed by Willis, who gets superhero abilities after surviving a train crash).
"Bruce is the most chilled dude. He is so relaxed, but he is bringing such a heaviness to the part," McAvoy said in a statement to IANS.
"That's beautiful, and something I haven't seen a lot in superhero movies: the weight, the toll that the work takes on them. And it's expressed so brilliantly by Bruce. His natural laidback-ness translates into something really sad in the character. David Dunn is this lonely man.
"All he really has in his life is his vigilante purpose and his son, and that's kind of it. There's such a purity and sadness in what Bruce is doing with that," he added.
The awaited sequel to "Unbreakable" and "Split" also stars Samuel L. Jackson and Sarah Paulson. Brought to India by Disney India, the film will open on Friday.