That cool Tony Awards moment when Jay-Z joined Alicia...

Jay-Z's electrifying reunion with Alicia Keys on what appeared to be a live duet of Empire State Of Mind at the Tony Awards on Sunday was actually pre-taped, a show official who wasn't authorized to speak publicly told The Associated Press.

The appearance of the rapper at Lincoln Center's David H. Koch Theater in support of Keys' musical Hell's Kitchen led to a boost of excitement inside the venue.

However, fans of the 54-year-old rapper were left fuming, as it now appears the duet was just a piece of Hollywood trickery that undercut the Broadway community's full-throated embrace of live singing and dancing. New York Magazine first reported on the pre-taped segment.

A representative from Jay-Z's Roc Nation and a producer at White Cherry Entertainment did not return messages seeking clarification on what happened Sunday night.

A senior publicist for the telecast also did not return requests for comment on Monday.

Jay-Z's electrifying reunion with Alicia Keys on what appeared to be a live duet of Empire State of Mind at the Tony Awards on Sunday was actually pre-taped, a show official who wasn't authorized to speak publicly told The Associated Press

Fans of the rapper in the audience at Lincoln Center's David H. Koch Theater were disappointed that his performance in support of Keys' musical Hell's Kitchen was all a ruse

Hell's Kitchen, which won two awards Sunday night — for star Maleah Joi Moon and Kecia Lewis, who plays her mentor — is loosely based on Keys' years growing up in the eponymous Manhattan neighborhood.

The show contains both classic hits and new songs from the singer–songwriter.

Keys is a producer of Hell's Kitchen but doesn't appear in the musical. The show ends with a rousing edition of Empire State Of Mind, though audience members normally aren't treated to a surprise appearance by Jay-Z, who released the song on his 2009 album The Blueprint 3.

Each best new musical nominee at the Tony Awards gets a slot performing, and Hell's Kitchen was first, with the cast performing a medley of songs — including Keys' hit Fallin' — from the show.

Keys added some star power when she appeared at the piano on the stage of the David H. Koch Theater and began singing her and Jay-Z's 2009 smash hit, which topped the Billboard Hot 100 singles chart.

She soon got up and went down the steps of the stage, into the orchestra seat section and then out the side of the auditorium.

'Had to do something crazy — It's my hometown!' she giddily shouted to the crowd as she exited the theater.

Moments later she appeared to join Jay-Z on some of the theater's marble steps, which generated wild applause from their fans at the ceremony.

'Brooklyn, New York City in the Tonys tonight!' Jay-Z added as he signed off at the end of the performance.

The audience inside the auditorium were shown live on television, but so far no photos have surfaced of the two performers together as they initially taped Jay-Z's appearance.

A version of their stirring conclusion to the song was beamed to the TV audience, while also playing on a large video screen above the theater's stage.

Keys was dressed in the same outfit she wore on stage, but Jay-Z was never spotted entering the packed auditorium.

The performance appears to have fooled some of the audience members at the Tonys, as they thought Jay-Z was performing just outside the doors, according to the New York Times.

CJay Philip, the winner of an excellence in theater education award at the Tonys, told the publication she was excited to see Jay-z for a 'second,' before realizing that the odd staging meant it was all a ruse, although she said her mother bought it and thoroughly enjoyed it.

Hell's Kitchen, which won two awards Sunday night — for star Maleah Joi Moon and Kecia Lewis, who plays her mentor — is loosely based on Keys' years growing up in the eponymous Manhattan neighborhood

Keys is a producer of Hell's Kitchen but doesn't appear in the musical. The show ends with a rousing edition of Empire State Of Mind

The song was originally released on Jay-Z's 2009 album The Blueprint 3. Alicia wasn't the original singer intended for the track, but later joined it and got a writing credit

After Alicia appeared on stage to start Empire State Of Mind with the cast at her piano, she got up and went into the audience then proceed to exit the theater

A video feed cut to Jay-Z on the marble steps of Lincoln Center's David H. Koch Theater. Alicia soon joined him, but that performance was taped earlier and only played on a video screen in the theater and on TV

Some of Jay-Z's fans were excited to see him on the screen, but many professionals inside the theater recognized that it was likely a pre-taped performance

'I was like, "Well, I’m glad mom enjoyed it,"' she said.

Wendall K. Harrington, a projection designer on Broadway who won a special Tony Award that evening, noted that people around her couldn't make out whether the performance was live or pre-taped, but she was savvy enough to immediately know what was going on.

'I was not fooled,' she said, citing her professional experience. 'I’m in the projection business.'

While some parts of the Tony Awards telecast are pre-taped — including technical awards handed out before the show, some advertising packages and often segments from the most-nominated plays — the strong feeling of those in the theatre is that the musical performances should be what audiences will see when they come to Broadway, with no trickery.