Adam Lambert and Kris Allen sing Kara's song tonight

By April MacIntyre May 20, 2009, 1:40 GMT

03/05/2009 - Adam Lambert -Season 8 of “American Idol” has rendered two distinctly different vocalists who promise to deliver vastly different performances. Kris Allen and Adam Lambert will be voted on for the season’s winner, both will bring their own individual styles to the same song, “No Boundaries.” .© Chris Hatcher / PR Photos

Tonight promises an interesting conclusion for "American Idol."

Season 8 of “American Idol” has rendered two distinctly different vocalists who promise to deliver vastly different performances.  Kris Allen and Adam Lambert will be voted on for the season’s winner, both will bring their own individual styles to the same song, “No Boundaries.”

Tonight’s show will be broadcast live on FOX (Tuesday, May 19, 2009, 8:00-9:00 p.m. ET live/PT tape-delayed).

Each arrangement reflecting the input of both Lambert and Allen, “No Boundaries” was written by Kara DioGuardi, Cathy Dennis and Mitch Allan; produced by Eman; and mixed by Mark Spike Stent. 

The song is published by Bug Music (BMI), EMI April Music, Inc. (ASCAP) and Matzoh-Ball Music (ASCAP) (adm. by Arthouse Entertainment/Bug Music, Inc.).

Both versions of the song will be available via iTunes after the two-hour vote-tallying finale on Wednesday, May 20, 2009 (8:00-10:00 p.m. ET live/PT tape-delayed). 

FOX announces that this season’s Top 13 performers will be joined Wednesday night by Black Eyed Peas, Cyndi Lauper, Lionel Richie, Santana, Rod Stewart and Keith Urban as they sing some of their greatest hits.

The winner of “American Idol” will receive a record contract with 19 Recordings.  All performers in the Top 10, including Kris and Adam, will take part in this summer’s “American Idol Tour” beginning July 5.