Sources close to production tell The Blast that the singers are separately recording original material for the hotly anticipated film’s soundtrack.
We’re told that while the legendary “Cats” music will, of course, be included, the film will also incorporate the new music.
Swift signed on to play "Bombalurina" while Hudson is taking on the role of "Grizabella" in the upcoming adaptation. The movie also stars Idris Elba, Rebel Wilson, Ian McKellen, Judi Dench, and James Corden.
"Cats" is directed by Tom Hopper and based on the T.S. Eliot poetry collection.
It is set for release on December 20.