Williams worked closely with celebrity vocal coach Eric Vetro, who has collaborated with top young musical talent like Ariana Grande, Shawn Mendes, and Camila Cabello, as well as La La Land duo Emma Stone and Ryan Gosling, to perfect her performance. Williams hopes this is only the beginning of her musical future: “I’d love to do more.… Even before this trailer’s come out, we’ve had so many people being like”—she slipped effortlessly into a flat Hollywood accent —“‘Does Maisie sing? Can she do a musical?’ Something in the universe is telling people that I have a voice, and I need to use it. So I’m very excited for the world to see what I can do, and I really hope that it leads to more things in the future. And if not, it would have been fun to do anyway.”

What kind of musical is Williams dying to do? One that highlights her talents beyond the austere world of Arya Stark and Thrones. Williams has a naturally zany streak, perhaps best highlighted by her stint as a compulsively watchable Vine performer. “Musicals and comedy go hand in hand,” she pointed out. “There’s so many people who are doing that so well. I’d love to do a [musical] film.”

Through this ad, Audi hopes to get the word out about its commitments to sustainability, including its CO2-neutral Audi e-tron assembly plant in Brussels and its goals to increase the sales share of electrified models and reduce global CO2 emissions by 2025. Though the urgent political themes of the ad—which sees Williams urging those around her to “let go” of the past and embrace a more sustainable future—are serious ones, Williams leaned on her funnier side in order to drive home some of the Frozen anthem’s more on-the-nose lyrics. “I’ve always seen myself as a little bit cheeky,” she explained. “The comments that I make or the way that I present my ideas is usually charged with a bit of cheek. So it made a lot of sense to be [singing] such an upbeat, lovely song, but really be saying a powerful message about the environment and our attitudes.…”

Speaking of which: What did Williams make of the popular, late-in-the-series theory that Game of Thrones, with its message of encroaching winter, was really a climate change allegory all along? She’s not quite buying it: “I’ve always seen Game of Thrones as pretty face value.… So in terms of the dual meaning and it being about the environment, it wasn’t something that I necessarily thought about myself.”

But Williams doesn’t mind that interpretation, or any conversation, really, that will get people talking about protecting the environment. “We cannot ignore the signs of climate change right now.… We’ll watch a fantasy show and question whether or not it’s a statement about the world that we live in—it just shows that we have to do something.”

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