Taylor Swift and Andrew Lloyd Webber compose haunting new song for 'Cats'

It's no secret Taylor Swift loves cats as much as she loves singing, so being able to combine her two loves for the movie "Cats" was, understandably, a dream come true.

Now, she's added her third passion -- writing music -- to the mix by teaming up with one of Broadway's most prolific composers, Andrew Lloyd Webber.

Webber, who composed the record-shattering musical adaption of T.S. Eliot's "Old Possum's Book of Practical Cats," worked his magic with Swift and gave life to a new original song for the film, "Beautiful Ghosts."

Swift will not sing the song in the main feature, but her studio version will play during the end credits. Instead, Royal Ballet principal dancer Francesca Hayward, who plays Victoria the White Cat, will do the honors.

While Victoria is a predominant character in the musical, the part doesn't include any musical solos because it's primarily a dancing role.

Webber expressed his excitement over Victoria's expanded role in the movie, saying, "When I first read the screenplay, the first thing I said was, 'We have to have a song for Victoria.'"

He says "Beautiful Ghosts" is now "an incredibly important and central part of the whole film.”

In a behind the scenes interview with Swift and Webber, the two opened up about their ambitious project.

"T.S. Eliot is such a specific type of writer and uses such specific language and imagery, and so, reading through, like, his work and everything I just really wanted to reflect that with [our song]," Swift explains.

"You can't write a modern lyric for 'Cats.' So, like, if you can't get T.S. Eliot," she grins while indicating herself, "Get T.S. -- I'm here for you."

"Cats," starring Swift, James Corden, Idris Elba, Jennifer Hudson, Ian McKellen, Rebel Wilson and more premieres Dec. 20, 2019.