Why Katy Perry and Lionel Richie Are Not Judging 'American Idol' Tonight

Luke Bryan is joined by guest judges Ed Sheeran and Alanis Morissette.

It was not a typical Sunday night on American Idol. With judges Katy Perry and Lionel Richie across the pond in England for the coronation of King Charles III, the ABC music competition show had to get creative.

Though Richie and Perry appeared live from Windsor Castle for a brief cameo, the regular judges had some A-list substitutes on the panel this week.

Ed Sheeran and Alanis Morissette stepped in to help out regular judge Luke Bryan as they offered commentary on the live shows for the Top 8. Sheeran also gave a special performance ahead of the release of his newly released album, Subtract

Perry and Richie performed for the official coronation concert for King Charles III on Sunday following Saturday's coronation ceremony at Westminster Abbey.

Richie previously teased to ET Idol's plans for including them in Sunday's episode.

"We are going to be live from the castle as only we could do, which is fantastic. I mean, let's just talk about Cinderella," Richie said. "... It'll cut back and forth to us, but I'm just going to say it's going to be an incredible experience."

Perry concurred at the time, telling ET, "We still have a job to do on American Idol, so we will be tuning in from Windsor Castle."

Richie and Perry previously shared that they did not pick their substitutes, but they were happy with the selections.

"To get Ed and Alanis to do this is just amazing," Richie said. "It just tells you to the power of the show. The contestants are going to love it... It's going to be good."

"I'm just so happy it's Alanis and Ed, because I'm a fan of both," Perry added. "It will be exciting to hear what they actually have to say and how they constructively critique if they have to."

American Idol airs Sundays and Mondays at 8 p.m. ET on ABC.

Although the actual anointment during the coronation ceremony was not broadcast publicly, plenty of special programming and footage from the ceremony is available to watch on CBS and Paramount+. Audiences are also able to view coverage on CBS News, including the concert featuring Perry and Richie on Sunday.