John Lithgow has been a fixture on movie (and even TV) screens for more than five decades, so he’s as professional as they come. When his role in new movie Jimpa called for him to be naked, because it’s something his titular character relishes, Lithgow immediately stripped down.

“John was so amped to do everything that was required, in terms of fulfilling this character and making the film,” director Sophie Hyde tells Entertainment Weekly at the Sundance Film Festival, which kicked off this week. “He was so excited by the idea of Jim, who he was, and the idea that he would get naked all the time. That was part of what appealed to John. And he was like, ‘I feel like it’s fantastic that he would be naked in the first few minutes of the film, and then it’s like whatever. Who cares? We now know who the character is.'”

So, yeah, it was “not difficult at all” to convince the two-time Oscar nominee that he should bring that aspect of his character to life. Really. The Good Luck to You, Leo Grande director said nudity came up in their first conversation.

“John just comes at character with this huge gusto,” Hyde explains. “He’s so excited, so rich and deep in his exploration, and part of that was being naked.”

Hyde didn’t want to spoil anything by giving away whether prosthetics were used.

“All I will say is that John is the most open, generous person, with his body and his heart and his soul, when it comes to making a story and a character. So that moment he just walks on in, he just drops it in front of whoever’s there — closed set, of course — and he just goes for it. He is absolutely wonderful.”

Lithgow costars in the touching drama alongside Olivia Colman and Aud Mason-Hyde. He plays a dad and grandfather nicknamed Jimpa, who left his family behind in Australia a lifetime ago so that he could live his life independently as a gay man and activist in Amsterdam. Colman’s Hannah and her non-binary child Frances reconnect with him over the course of the film.

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As for Colman, the Oscar winner had equally kind things to say about the star of movies including Footloose, Shrek, and Conclave.

“It feels like you’re a best friend on day one,” Colman tells EW at the film festival. “It was instantly cozy.”

Lithgow notes that the two “have a little history,” because they “spent a morning shooting one scene from The Crown, when she was the queen and I was Churchill on my deathbed.”

They shared the screen in a 2019 episode of the Netflix drama that famously shuffled its cast to portray characters at various ages. His Churchill appeared in a single episode the Emmy winner, just as Colman was taking over the part of Queen Elizabeth II from Claire Foy.

“It’s in our rider to only work together on deathbeds,” Colman teases.

“Don’t give everything away,” Lithgow cautions her. Kindly, of course.

Reporting by Gerrad Hall and Alamin Yohannes