Here we are, at the second-to-last (or is it?) episode of American Idol ever. The whole 15th season has been nostalgic, but the nostalgia has gone into overdrive this week as the show takes a well-deserved victory lap. And it's a great send-off, with an evenly matched final between La'Porsha Renae and Trent Harmon. I have no idea who's going to win. America has a very tough choice to make.

The show opened with the Top 3 together singing Kygo's heart-tuggingly appropriate "Stole the Show," which goes, "We used to have it all, but now's our curtain call/So hold for the applause, oh/And wave out to the crowd, and take our final bow/Oh, it's our time to go, but at least we stole the show," hearkening back to the halcyon days of when American Idol was the biggest thing on TV.

The first round tonight was a big moment, where the contestants debuted their original singles. This is the winner's single, Trent or La'Porsha's own "A Moment Like This."

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Trent went first, with his song "Falling." It's a Southern-fried, bluesy sort of number that reminds me of a Justin Timberlake ballad, or Alicia Keys' "If I Ain't Got You" with its swung, rat-a-tat phrasing. And Trent looked the best he's ever looked in his all-black ensemble.

Next up was Dalton with "Strike A Match," a soft alt-rock song that underwhelmed.The sweeping synths were nice, but Dalton can rock harder than this. It'll be exciting to see if he turns up the guitars and screams a little bit outside of the confines of American Idol.

La'Porsha's song "Battles" is the best of the bunch. It's an inspirational song about not giving up, and La'Porsha sings it from a real place — it hasn't been an easy road for La'Porsha to get to where she is.

Then the votes are in, and the third-place finisher is determined: Dalton Rapattoni. Trent and Dalton hug several times, and Dalton doesn't seem too sad. His smile seems genuine, like he's truly grateful to have made it this far. He's a good kid, this Dalton Rapattoni.

We jumped quickly into Idol creator Simon Fuller's picks. For Trent, Fuller chose Harold Melvin and the Blue Notes' Philly soul classic "If You Don't Know Me By Now," which Trent beasted. He showed that even though La'Porsha's the favorite, he won't go down without a fight. This will be the "closest race in Idol history, " Keith Urban says. Simon Fuller made an excellent choice for Trent. And I love his purple velvet blazer. After so many fashion missteps this season, Trent really turned his swag on tonight.

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Then La'Porsha tackled Dionne Warwick's "A House Is Not A Home." It's a big show-stopping ballad that La'Porsha sings the hell out of, starting with her head voice before going into full-throated belting. I personally didn't love the song, but I loved La'Porsha's performance. Simon Fuller crushed it with his choices.

For his last impression, Trent chose Sia's "Chandelier," which he killed two weeks ago, and he killed it again tonight. He turned it into a ballad, and the crowd went wild. He got maybe the biggest cheers of the season. I think they were cheering for the metal tips on his lapels that made his jacket look it had devil horns.

La'Porsha closed the show with Rihanna's "Diamonds" (which, like Trent's song, was written by Sia). She had on a studded dress that turned her into a diamond, and the crowd broke out into a "LA-POR-SHA" chant. Harry, the lyrics guy, asked who she's singing about when she sings "you," and she said her baby. AWWWWW.

So as we knew it would be from pretty early on, it's Trent and La'Porsha in the final. Who do you think is going to win?

The big reveal comes as part of the series finale, tomorrow at 8/7c on Fox.