Trent Harmon, Dalton Rapattoni, La'Porsha Renae to compete for 'American Idol' crown

Three-night series finale week kicks off with 90-minute retrospective, 'American Idol: American Dream,' Tuesday, April 5, on FOX 

Alums Kelly Clarkson, Carrie Underwood and Jennifer Hudson to perform in two-part grand finale broadcast live Wednesday, April 6 and Thursday, April 7

Winner announced Thursday, April 7 

Trent Harmon, Dalton Rapattoni and La'Porsha Renae are this season's "American Idol" top three finalists, after it was revealed Thursday that MacKenzie Bourg received the fewest votes.

Next week, someone's life will change forever, as "American Idol," the cultural phenomenon that changed the face of television and created some of today's biggest music stars, will kick off a three-night grand finale. On Tuesday, April 5 (8-9:30 p.m. ET/PT), "American Idol: American Dream," the can't-miss, 90-minute retrospective will feature host Ryan Seacrest, current and former judges, former "American Idol" contestants, and the behind-the-scenes team sharing personal memories, as they reflect on what the show has meant to them and how it became the groundbreaking series it is today.

In addition to Seacrest, original "American Idol" judges Simon Cowell, Paula Abdul and Randy Jackson offer never-before-revealed stories about how the show came to be.

The following night, America's most crucial - and last-ever - vote will take place when the remaining finalists battle it out live from Dolby Theatre on Wednesday, April 6 (8-9 p.m.). "American Idol's" two-part grand finale will be filled with surprise appearances and star-studded performances, including winners Kelly Clarkson and Carrie Underwood, along with Jennifer Hudson, who return to the stage one last time to perform on Thursday, April 7 (8-10:06 p.m.). The farewell celebration will continue, as "American Idol" pays tribute to the past 15 seasons, the talented contestants and the millions of fans who called, tweeted, texted and championed their favorites, before the 15th "American Idol" is crowned.

Viewers at home have five ways to vote for their favorite singer, including the SuperVote online at www.americanidol.com/vote; SuperVote on the FOX NOW app; Google search voting; text vote (SMS); and toll-free voting. All voting rules and frequently asked questions are available online at http://www.americanidol.com/voting-faq.