Keira Knightley and Writer-Director Camille Griffin Talk Exploring Motherhood at the End of the World in ‘Silent Night’

Keira Knightley was “incredibly pregnant” the first time she read writer-director Camille Griffin’s script for the comedic holiday horror-drama “Silent Night,” and recalls finding the unusual tale of a Christmas Eve gathering the night of a coming apocalypse “absolutely, hysterically funny.”

She read it again months later — sleep deprived and with her six-week-old daughter in tow — and still found it hilarious.

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But by the time production started, her daughter was five months old. Suddenly, the parental strife and absurdist life-or-death decisions peppering the script took on a very different light.

“I was like, this is not funny! What the fuck was I on? This is the opposite of funny!” she squeals in bafflement.

As a new parent herself, the questions the film poses about the lengths one is willing to go to to protect one’s children took on a new, unshakeable weight.

In “Silent Night,” Knightley’s character Nell and her husband Simon (Matthew Goode) host a group of old college friends for an intimate Christmas gathering that begins jolly, but veers somber as it becomes clear that the party has been called to celebrate their last night on earth. Toxic clouds of poison are sweeping the world, bringing gruesome deaths to all those who encounter them, and the families must choose how to face the onslaught.

The backstory is never fully explained, but that’s alright: What’s really being explored here isn’t the horror of some sci-fi scourge, but that of what Knightley terms the “maternal catastrophe” — the birth, along with one’s child, of a terrible knowledge of everything that could go wrong and harm them.

“The maternal experience is deeply under-explored on screen, and particularly that side of maternity where you bring life into the world, but at exactly the same time you bring a fear into the world that is almost overpowering,” said Knightley.

“This real knowledge of every disaster that could strike you and your family becomes incredibly real as soon as you become a mother. Maternity is constant struggle and sacrifice, and a constant battle of how much of yourself you’re still allowed and how much of yourself you have to destroy for your child. To me, the film explores that.”

For two decades, Griffin fought to try and make a film about “the dysfunction of the middle classes” — a necessary counterpoint, she felt, to an industry mired either in period dramas about the posh or stories of the working class, with not much in between.

The idea to move on from that dream to “Silent Night” came from her experience on the set of Taika Waititi’s “Jojo Rabbit” with her son, Roman Griffin Davis, the scene-stealing young star of both pics. Watching Waititi at work, she developed a keen appreciation for his ability to use comedy to address difficult subjects.

“A lightbulb went on that was extraordinarily powerful to experience. I thought: ‘Wow, I can talk about anything if it’s funny,’” she explains. “So I decided that I would make a movie about how painful it is to be responsible for children when there’s so much you can’t protect them from.”

Griffin’s own three children, Roman, Hardy and Gilby Griffin Davis, play Nell’s three young boys, adding a layer of unscripted familial chaos, camaraderie and verisimilitude to the picture.

It was a practical choice to save on budget, but also what felt like a necessary one.

“The children were going to have to go on quite a challenging journey with the subject matter and material that was potentially traumatizing. I had to cast my own children because I didn’t want to do it to another person’s child — I knew that my children would be safe and it wouldn’t traumatize or hurt them,” she said.

The on-set and on-screen presence of their real-life chaotic, foul-mouthed, ebullient family dynamics — the “dysfunction and the love,” as Knightley calls it — gave her the space to carve out a maternal character that skirts stereotypes, a role Griffin says she feels the British star couldn’t have mined the depths of without her own recent maternal experiences.

“You very often view mothers as almost a kind of angel in the room, always self-sacrificing, always loving. On film, they’re these silent creatures that just kind of disappear,” Knightley said. “What I loved about this film is you feel their rage, you feel their sexuality, you feel their desperation to probably take drugs and get fucked, but also you feel their knowledge that at the end of the day, even in death, still what they’re thinking about above all is their kids.”

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