Dawn French and Jason Donovan will join the composer at the judges' table for the new talent ITV1 talent show, with a guest judge joining the trio for each live broadcast.
Donovan, who assisted at callbacks for the show earlier this year, has spoken of his excitement about the "cracking talent" the judges have encountered so far.
Amanda Holden will also appear as host of the series, which aims to search for a lead in a new production of the composer's rock opera Jesus Christ Superstar.
Superstar will debut on ITV1 in early July.
Chris Moyles, Mel C and Tim Minchin have all signed up for parts in the revival, which will start on September 21.
Watch the trailer for Superstar below: