Hotel Mumbai takes place over the course of three days inside the Taj Hotel during the Mumbai attacks in 2008 — during which time the staff and guests worked together to survive. 

"The staff and guests performed miraculously," actor Jason Isaacs told The Hollywood Reporter at the Toronto Film Festival, where the movie is screening. "They were uninterrupted by police, so for three days the terrorists have free rein of the hotel. It's a bunch of intersecting stories based on thousands of interviews."

Isaacs said the film captures "the essence of this miraculous outburst of humanity and bravery that kept so many people alive."

"It's gut-wrenching to see what they went through, but the beauty of it, I suppose, if you can find the silver lining, is that it's really about human resiliance and survival, and people coming together," actress Nazanin Boniadi added.

"You're dealing with class divides," said Dev Patel, who plays a waiter from the slums of Mumbai. "He kind of has to go over and above to help the people that he's in charge of," he said of his character.

Patel, who is a British native of Indian decent, said the hotel is a great source of pride for the people of Mumbai, adding, "once this horrific event happened, within three weeks they got it fully functioning and running again to make a point, that you can't bring us down."

"We kind of shared the brutality," Patel continued. "Between one person, we would have crumbled, and that's the story of the film. It's an ensemble. It's about everyone in that hotel: guest, staff, alike."

Watch the Hotel Mumbai cast discuss the film and the real events on which it is based and Patel recount his heroic tale of saving director Anthony Maras' thumb after it was accidentally severed.

Dev Patel Saved 'Hotel Mumbai' Director's Thumb | TIFF 2018