'The Sing-Off' Finale: Pat Benatar, Pentatonix, 98 Degrees to Perform

Neil Giraldo will join Benatar onstage, and show judges Jewel, Shawn Stockman and Ben Folds will each perform with the acapella competition finalists.

Grab your pitch pipes: The Sing-Off has announced the lineup for its two-hour finale on Monday night.

Special guests Pat Benatar and Neil Giraldo will sing their 1984 hit “We Belong," and season three winners Pentatonix will also return to the stage they conquered in 2011.

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Additionally, Sing-Off host Nick Lachey will be joined by his fellow 98 Degrees members Drew Lachey, Justin Jeffre and Jeff Timmons to perform “I’ll Be Home for Christmas,” from their 1999 holiday album, This Christmas. He also serenades the season's new judge Jewel into a duet of “It Had to Be You."

And following Sing-Off tradition, the final episode pairs each judge with one of the remaining a capella groups in the competition. Jewel will perform with professional country group Home Free, Shawn Stockman will take the stage with gospel-infused collective Ten, and Ben Folds will join performing arts high school group Vocal Rush onstage.

All seven previously eliminated groups -- The Filharmonic, VoicePlay, acoUstiKats, Element, Calle Sol, Street Corner Renaissance and The Princeton Footnotes -- will return to perform as well.

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The final night of the revived a capella competition will feature holiday songs as part of its set list -- an element sorely missed during season three's finale. The episode will crown a season four winner, who will be rewarded with a $100,000 prize and a Sony Music recording contract -- plus the top spot on The Sing-Off's first tour.

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