One big question looms over the season 19 finale of “American Idol”: where was Arthur Gunn?

The “Idol” contestant was slated to perform a duet with Sheryl Crow during Sunday night’s episode. Instead, viewers saw Top 16 singer Graham DeFranco onstage with Crow performing what seemed to be a hastily put-together number. Gunn was not seen during any part of the telecast.

Gunn came in seventh but was the runner-up on the last season of “Idol.” He was brought back this year in a surprise move that shocked fans.

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“Idol” judges Lionel Richie, Katy Perry and Luke Bryan are just as in the dark as everyone else. During a virtual post-show Q&A, Richie confessed he and the other judges “don’t even know what happened” with regards to Gunn’s absence. Perry kept it vague, saying that “American Idol” is a “spicy show.”

“It’s a live, three-hour show. And, quite honestly, we’ve had a very colourful season. Curveballs galore,” she added. “But Graham DeFranco? I mean, killed it. Sang so well, and I was so glad he was there.”

Bryan did admit that DeFranco’s performance with Crow was put together at the last minute. “He literally came to cheer,” the country singer said. “He was there to support Chayce, and we’re pulling him out of the crowd going, ‘You’re gonna sing with Sheryl Crow.’ And he’s like, ‘Hell yeah!'”

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Curiously enough, Arthur is also missing from a list of Top 10 contestants that fans can vote for to join the Top 2 finalists that will perform on “Live! With Kelly and Ryan.” As Arthur finished in seventh place, his name should be included. 

Gunn offered a vague response in the early hours of Tuesday morning. He credited “personal morals” and “unpleasant environmental experiences” for his no-show.

“Well, let’s just say I missed my opportunity to sing with legendary [Sheryl Crow],” he wrote on Instagram. “What happened is not much to discuss at this point. I would like to make it up and invite [Crow] to perform couple of songs on the July 30th at @thecotillion. It was last minute decision but I couldn’t help but say no cause of some personal morals and values due to unpleasant environmental experiences.”

You can read his full statement below.