Universal Pictures is offering a peek behind the scenes—excuse me, “a look inside”—of Tom Hooper’s Cats movie with commentary from the cast, which includes Jennifer Hudson, Ian McKellen, Idris Elba, Rebel Wilson, Jason Derulo, and cat lover Taylor Swift. Judi Dench, who will play a gender-flipped Old Deuteronomy, recalls how she was supposed to play Grizabella and Jennyanydots in the original London production of Cats in 1981 but had to bow out due to an injury: “I thought that was my history with Cats, but it turns out not to be.”

James Corden adds that “these are people, but they’re cats, and this is kind of blowing my mind.” Thanks, James Corden!

Perhaps the most intriguing revelation is that the movie is using enormous, real sets scaled so that the human actors look cat-size, rather than relying on CGI to create the environments. That’s not to say the film isn’t also getting a special-effects boost. The actors will be aided by “digital fur technology to create the most perfect covering of fur.” We don’t get to see it in action here, presumably because they’re not showing the actors in character until this week’s trailer drop, but the expectations for digital fur consistency have never been higher.