Pop's biggest stars are gearing up for the Grammy Awards later, with performances due from Pharrell Williams, Katy Perry and AC/DC.
Madonna will make her live return, playing music from her new album Rebel Heart; while Ed Sheeran will duet with Herbie Hancock and ELO's Jeff Lynne.
Rihanna, Kanye West and Paul McCartney will also give the first performance of their collaboration, FourFiveSeconds.
But Taylor Swift has excused herself from performing at the ceremony in LA.
The star, whose single Shake It Off is up for record of the year, says she is too "wrapped up and entangled" in planning her world tour to choreograph a Grammy performance.
"I'll be there having a dance party/rage fest in the audience," she added.