King Charles grills Lionel Richie as he makes surprise appearance on 'American Idol'

King Charles and Queen Camilla stunned fans as they made a surprise appearance on 'American Idol' with the show's judges, Lionel Richie and Katy Perry on Sunday.

The King and Queen were all smiles as they joined the hosts of the hit music show from Windsor Castle.

The show's official Instagram page breaks the news with the clip, captioning: "Surprise! Their Majesties King Charles III and Queen Camilla join @lionelrichie and @katyperry from Windsor Castle!"

Singer Katy Perry, who performed at the Coronation gig alongside Lionel Richie, also shared the video. She captioned the clip: "£100 to whoever had this on their 2023 #idol bingo card."

The singers, in the clip from Windsor Castle, delighted viewers as they shared about the "incredible" historical event they witnessed and said they thought of how they could bring "something different to the show" as Perry suddenly backed out of the way.

Richie left Perry stunned as he told her: "Excuse me, Katy. I have a surprise," with Perry giving an "Oh goodness" before bowing to their royal guests.

The 74-year-old monarch then uttered an "All Night Long" song reference then casually grilled Richie about how long they were going to be filming.

"I just wanted to check, how long you will be using this room for?" King Charles said with a sweet smirk and laugh for the bit, telling Richie, "Thank you so much. You're brilliant as always," and then acknowledged Perry as well, as Camilla smiled throughout the clip.

They spoke of the "party next door," meaning the coronation concert, and Charles joked, "Oh, you've heard of it?"

He added, "I better take you to the party, but you're busy with these other things."

Richie responded as saying: "It's an Honor to Perform at Wonderful King Charles' Coronation." Charles said: "Bless you."