Dame Judi Dench claims the cast of 'Murder on the Orient Express' were forced to be friends because they were stuck on a train.
The 'James Bond' actress is part of an all-star cast, which also includes the likes of Johnny Depp, Penelope Cruz, Daisy Ridley, Willem Defoe and Michelle Pfeiffer, in a new big screen adaptation of the Agatha Christie classic, and they had a "glorious" time together, even though they rarely got a break from one another during down time from filming.
She told the Daily Mail newspaper: "We had the most glorious time.
"You had to be part of the company, because nobody could get off!"
The 82-year-old actress particularly enjoyed Josh Gad's company, branding him "the naughtiest".
But she added: "Not only that: he stayed in the hotel I use when I am up in London. He's ruined my reputation!"
Judi - who plays a formidable Russian princess in the movie - thinks it is "essential" to have fun on her movie sets and admitted it's one of the reason why the new film marks her tenth collaboration with director Sir Kenneth Branagh, who also stars as infamous Belgian detective Hercule Poirot.
She said: "I don't want to work with anyone who hasn't got a sense of humour.
"It's essential! I simply am not interested in working with them if they're miserable by nature.
"It's like the froth on the top of Guinness. You have to have the froth, and then you get to the real thing.
"You discover people through larks. I always get into trouble with Ken - and I like that!"
Despite the big names in the cast, Kenneth admitted some of them were nervous about meeting Judi - who played M in seven 'James Bond' films between 1995 and 2012 - though she doesn't understand why.
She said: "I don't know why I should get that reputation - I've never been grand in any way.
"I don't think there's anyone I've ever worked with, in 60 years, who would say that I've ever been very grand, or frightening.
"Well, I like to frighten Daniel Craig. And Pierce Brosnan. I used to frighten the bejeezus out of them. But apart from that... "