‘American Idol’ finale updates: Trent Harmon wins the last title ever

"American Idol" went out big Thursday night. About 13.3 million viewers tuned in to the finale of the long-running singing competition series, which saw Trent Harmon crowned the 15th and final "Idol" in a surprise victory over fellow Mississippian La’Porsha Renae. It was the most-watched show of the night among viewers under 50, according to Nielsen.

The president offered his thanks, Brian Dunkleman forgave Ryan Seacrest, JLo reminded everyone how it’s done, and Simon Cowell and his chest hair were once again reunited with Randy Jackson and Paula Abdul.

Oh, and in a big upset, Trent Harmon won the thing.

“American Idol� had promised us a night of surprises. But the biggest surprise of the show’s final finale wasn’t the fact that Season 1 co-host Brian Dunkleman returned to make his peace with Ryan Seacrest, or that Carrie Underwood showed up to duet with Keith Urban, or that Simon Cowell strolled out to make Paula Abdul and Randy Jackson cringe, or that a cute little girl from New Orelans’ Ninth Ward turned up to sing “What a Wonderful World� alongside Harry Connick Jr.​

It wasn’t that every “Idol� winner in its 15-year history and a slew of contestants who hadn’t won returned to the show’s stage to perform. (It would probably take me less time to list the contestants who didn’t show up than the ones who did.) It wasn’t even that Larry “Pants on the Ground� Platt or William “She Bangs� Hung (and um, was that Sanjaya?) came back to do their strange things.

No, the biggest shocker of the “American Idol� Season 15 finale turned out to be the winner: Trent Harmon, the 25-year-old Mississippi farm boy and waiter at his family restaurant, the earnest fellow who trained himself not to make silly faces when he sang and wrote every word the judges ever told him down in a tattered leather-bound journal, the guy who suffered through Hollywood Week sweating and struggling with mono and still managed to make it all the way to the finale, crossed the finish line to snatch the crown away from the distinctive head of La’Porsha Renae on Thursday night.

The introduction number:

The return of first season co-host Brian Dunkleman:

The last two finalists perform: "It Takes Two:" 

There was a bit of confusion in the end of the show. Just before the show wrapped, executive producer Nigel Lythgoe came out to prep the audience for an emotional closer, in which the Idols and the audience were to sing Kelly Clarkson's "A Moment Like This." 

Instead the confetti blast at the end was so powerful that we couldn't see anything. We saw about a handful of finalists onstage sing the song as people hugged and embraced runner-up La'Porsha Renae. The lights then faded as the production crew came out to join the onstage party. Was there a singalong? We're not sure. Were we blinded by confetti? Yes. Will we miss "Idol"? With all our hearts. 

Mississippi farm boy Trent Harmon, 25, was just crowned the last "American Idol," stunning a crowd that believed La'Porsha Renae was the favorite. 

Here's his performance from last night.

The crowd inside the Dolby Theatre erupted when Simon Cowell surprised everyone by joining Randy Jackson and Paula Abdul on stage, alongside Ryan Seacrest. One word to describe the reaction? Nuts! Paula and Randy were first to appear to present Ryan with a parting gift: a giant neon "American Idol" sign the host said he would jokingly place on his nightstand. When Ryan asked Paula what she would remember most, the original Idol judge said "probably hitting Simon." Ryan added: "He did drive us all a little crazy."

And just as Ryan told the audience Simon couldn't make the finale, the vocal judge walked on stage and stunned the crowd. "Thank you America for inviting us into your homes, thank you to the contestants and to Fox for actually putting us on air," he said, while referring to Randy and Paula as "best friends." 

Simon added:"I’m feeling quite emotional now." 

So are we, Simon, so are we.

But then it happened.

Oh, J.Lo, you're sneaky! The singer-actress-Idol judge pulled a bait and switch during the finale when the audience was led to believe she wouldn't be performing live. Instead, the audience and viewers were treated to a taped performance. And they weren't happy about it. No clapping. No dancing. Lots of groans in the balcony when people realized she wasn't coming out -- until she did! 

J.Lo isn't the only one who gets "goosies." We got goosebumps when the "Idol" alums made an emotional appearance to kick off the finale. People were sobbing in their seats. The energy inside the Dolby Theatre is unreal. People are everywhere, production crew and staff are crowding all the doors with their phones out. The aisles are packed. Every inch inside the theater is covered with spectators. Wow, just, wow. 

Making a surprise taped appearance on the series finale, President Obama had a message for viewers: go out and vote during this election year. "I believe it should almost be as easy as voting on 'American Idol,'" Obama told viewers. "Not all of us can sing like Kelly Clarkson, but all of our voices matter." Fair point, Mr. President. 

When Fox started the American version of a British singing competition 14 years ago, the success of "American Idol" was so big, so immediate and so utterly unexpected that it essentially broke television.

Pretty much everything that's happened since, from "Keeping Up With the Kardashians" to "Transparent," from Sundance Channel's artisanal content to Netflix's binge model, is, at least in part, a product of the "American Idol" aftershock.