Glee Season 4 finale airs Thursday night on Fox, just after American Idol 2013 announces its finalists this year. Spoilers we've rounded up indicate big songs will be featured in this special Glee episode. "To Love You More" by Celine Dion will be tackled. Meanwhile, finale spoilers include a mystery character, who is reportedly leaving the show choir series even before it tackles the graduation period. Who could this be?

Glee Season 4 Finale Scoop: New Directions vs Jessica Sanchez? (Fox/Glee)

Considering reports of Heather Morris' pregnancy, many viewers believe it's her character Brittany S. Pierce who will be gone by Season 5. There are rumours that Brittany's appearances will be significantly reduced, but she will stay on in the show.

Fans of Rachel Berry can relax, it is not likely this character will be gone next year. Lea Michele has hinted on Twitter recently her character will still be a large part of Glee Season 5.

On other developments in the finale, we expect a conclusion to the "catfishing" arc involving Ryder. There is also the matter of Blaine wanting to propose to Kurt. Rachel shows up for a second callback for a Broadway revival of "Funny Girl," the role she claims was cut-out for her.

Glee Season 4 Finale Songs, Spoilers: Regionals with Jessica Sanchez (Fox/Glee)

Glee Season 4 finale: What songs will American Idol alum Jessica Sanchez sing?

American Idol 2012 alum Jessica Sanchez will guest star in the Glee Season 4 finale as aspiring diva Frida Romero. Her show choir Hoosierdaddies will be competing with the New Directions in the Regionals.

Scroll down for the list of songs that will be featured on the much-awaited finale, called "All or Nothing." This episode airs Thursday, May 9 at 9pm on FOX.

Here is the list of the Glee Season 4 finale songs:

"To Love You More" by Celine Dion, performed by Rachel Berry
"Clarity" by DJ Zedd, performed by Frida Romero (Jessica Sanchez) and the Hoosierdaddies [Scroll down to listen]
"Wings" by Little Mix, performed by Frida Romero and the Hoosierdaddies
"I Love It" by Icona Pop, performed by Tina, Brittany, Unique and the New Directions
"Hall of Fame" by The Script, performed by Artie, Sam, Jake, Joe, Ryder and the New Directions
"All or Nothing," an original song for the episode, performed by Blaine, Marley and the New Directions

LISTEN: Glee Season 4 Finale Songs feat American Idol 2012 Runner-up Jessica Sanchez

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