Shyamalan directed McAvoy's 'Split' personas separately

M Night Shyamalan's latest movie "Split" features James McAvoy as a man with 23 different personalities and the director said he shot every persona separately.
Shyamalan said that he did so to get the best performance out of McAvoy, reported Digital Spy.
"I kept one character on one day, another character on another day. For me it wasn't very different a thing to direct because I'm doing the exact same thing for each character and actor - talking through why I wrote it, what is their meaning in the movie and waiting to see the click in their eye," he said.

"So I'm like, 'Great, thank you. I'm going to have the next actor come in for the next role', but it was still James. He had to do that many more times the prep."
Co-starring with Anya Taylor-Joy as a girl kidnapped by McAvoy, the actor traverses different ages and genders, from small boy Hedwig to adult female Patricia.