Christmas Karma star Kunal Nayyar has joked he could be "as grumpy as I wanted" as a modern-day version of Scrooge in the new festive film, while director Gurinder Chadha said that no one recognised The Big Bang Theory star on set because of how thoroughly he disappeared into his character.
Released in cinemas on Friday, 14 November, Christmas Karma, written and directed by British filmmaker Chadha (Bend It Like Beckham, Blinded by the Light), is a unique and exuberant retelling of one of the greatest Christmas stories of all time - Charles Dickens' A Christmas Carol.
London-born, New Delhi-raised actor Nayyar plays Mr Sood, the film's Scrooge equivalent, an immensely wealthy British Indian businessman whose riches have made him hardened and heartless. He confronts his demons as he goes on a journey with the ghosts of Christmas past, present and future, played by the brilliant Eva Longoria, Billy Porter and Boy George, learning the true meaning of Christmas along the way.
Chadha said her inspiration for writing Christmas Karma came from Frank Capra's 1946 classic It's a Wonderful Life.
"A few years back I had watched it for the 500 millionth time and I was like, I want a film that makes me feel just like that film. So I thought, 'OK, if I made a Christmas film, what would it be? What would it look like?'", she told RTÉ Entertainment.
"I took inspiration from Charles Dickens, just as Frank Capra had, went to his house in Clerkenwell in London, walked around, spoke to Charles Dickens, and said, ‘OK, if you were me living today, what would you do, Charles?’
"And out of that came the story and the story of Sood, which is actually based on a couple of people, real life stories that I know. Once I got that, then everything just started falling into place and I wrote the script in about two weeks."
Heading up the cast as the crotchety Sood was "a lot of fun", Nayyar said, although it took a bit of work maintaining his stern demeanor in the midst of all the festive cheer on set.
"I could be as grumpy as I wanted and not feel guilty about it for one second!", he joked. "I mean, you know, it took a little focus, obviously, because between takes, everyone's jumping around and enjoying themselves, and I'm just, ‘Where's my coffee?’ There was a joy in it too, but of course it took a lot of focus."
"It meant that he didn't get asked for selfies all the time!", Chadha interjected. "No one recognized him."
"Yeah, it was really nice though, too," Nayyar, who had his breakthrough role as Rajesh Koothrappali in the huge US sitcom The Big Bang Theory, added.
The ensemble cast also includes Leo Suter and Pixie Lott as Bob and Mary Cratchit, Hugh Bonneville as Bob Marley and Eva Longoria, Billy Porter and Boy George as the ghosts of Christmas past, present and future, respectively.
"How blessed was I?", Chadha said of the starry cast she brought together for the film. "People just really warmed to the script, and the idea of what I was trying to do, and trying to say about today.
"Eva Longoria is Mexican, she's brought the whole Day of the Dead culture to the film. Billy Porter, the gospel culture. Boy George, just that idea of being a pop star who's been through so much pain [and] come out the other side. Everyone brought their own life struggle."
Chadha's Christmas Karma is a pure and joyous celebration of multicultural London and contains powerful messages of hope and inclusion.
"Christmas is about charity, it's about giving, it's about being human, empathetic," she said. "And that's true of every religion. I've never seen it as anything but a time for all of us to come together and believe in those values because being a Sikh, those are the same values we have.
"I want people to go away realising that there is more that unites us than separates us. After the terrible year that we've had, and we've seen so much suffering this year, it's a timely reminder that to be human is to have empathy and it is to sympathise and give.
"And that was Dickens' message, that's my message, that's what Sood learns at the end of the day. And if we want to build societies, particularly for our kids, to live in and thrive in, because I've made the film actually for my kids, we need to understand that we are all connected and that's how it's going to be."
Nayyar said that starring in this film has taught him some lessons as a person and an actor.
"I think everyone deserves redemption, everyone deserves forgiveness, everyone has an opportunity to redeem themselves, and I think Christmas is a perfect time for that," he said.
"Christmas is a perfect time to come together, to forgive, to celebrate love and joy and, like Gurinder said so astutely - bring together people who have differences.
"And this is the film - Christmas Karma is not just sad and about pain. Its ultimate message is actually about love and joy and music and putting your differences aside to come together."
Christmas Karma is out in cinemas on Friday, 14 November.