The forthcoming Garth and Trisha duet that will probably surprise you

Fans have never quite gotten enough of Garth Brooks and Trisha Yearwood singing together. But there’s a new recording few saw coming: they have a song on the Spinal Tap II: The End Continues soundtrack.

Hang on, it gets better: they’re on track #9, titled “Big Bottom.” They are in good company, with Elton John and Paul McCartney both appearing on the soundtrack as well, which is set to drop along with the film on Sept. 12.

The new mockumentary about a fictional rock band picks up 41 years after 1984’s This Is Spinal Tap, when the estranged band is forced to get back together for a final concert. No word on whether Garth and Trisha might appear in the film.