Here are five things to look forward to during the final episode of season 13:
1. The three judges will finally perform together.
"It was a blast," Harry Connick Jr. told PEOPLE on Tuesday of pre-taping his performance of Cyndi Lauper's "True Colors" and Fleetwood Mac's "Go Your Own Way" with his fellow judges, Jennifer Lopez and Keith Urban, as well as mentor Randy Jackson. "Jen chose 'True Colors' but I don't know who chose Fleetwood Mac. Being up there with them performing after talking about it for so many months was just great."
2. Caleb Johnson will perform with Kiss.
"I rehearsed with Kiss last night and they were absolutely amazing. They are some of the nicest, funniest people I've ever met. They were so insightful and gave me a lot of good feedback," Johnson told reporters. "I heard that they spent $25,000 on pyro for the show tomorrow and we rehearsed it and it was literally like Fourth of July, just [boom, boom, boom]."
3. Jena Irene will perform with Paramore.
"I haven’t rehearsed with them yet, but it should be good," Ascuitto said. "I hope I get [lead singer Hayley Williams's] number so we can text all the time. I’m a fangirl a little bit. I’ve loved that band since I was 12 years old, so there’s going to be a lot of things that I would like to talk to her about, but so little time."
4. The Top 13's girls will perform with Demi Lovato – but without MK Nobilette.
"Hey everyone I won't be in the finale this year due to illness but don't worry! I will still be on tour," Nobilette (the FOX reality singing competition's first openly gay contestant) Tweeted on May 19.
But the rest of the girls are excited to perform with the "Neon Lights" singer.
"Demi is extremely hardworking. She came right into the rehearsal, said 'hi' to everyone and learned all of our names, which was really nice," Asciutto said. "You can tell that she wants to put on the best performance she possibly can."
5. The 13th winner of American Idol will be crowned!
"It is going to be close, I would imagine," Connick said of it coming down to Asciutto and Johnson. "It is like a boxer versus a puncher and it is so cool. I think it is a matter of preference, really. It is not a matter of who did better. It is who you like more and who is going to vote for their favorite."
The American Idol finale airs Wednesday (8 p.m. ET) on Fox.
Michael Becker / FOX