'The Sing-Off' Recap: A Party Playlist and a Proposal Rock Week 1 (Video)

THR recaps the very high and very low notes of NBC's a cappella competition, revived after two years off the air and welcoming Jewel as a (really great) judge.
The Filharmonic on "The Sing-Off"

The Sing-Off returned to NBC this week with ten groups, three episodes and plenty of high notes to kick off its fourth season – a doo-wop One Direction cover, a party-playlist opening number and an onstage proposal among them.

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The breakout personality thus far is none other than Jewel – the musician fits perfectly between Boyz II Men's Shawn Stockman and a cappella mastermind Ben Folds, and all three of them dish out quality commentary on everything -- from the courage of an arrangement to the cohesive personality of an ensemble. Their critiques are collectively constructive to the group, critical enough to help them improve their future performances, yet friendly enough for viewers watching for the first time to understand the mechanics of what they have just seen and heard.

Here's what happened on the first week of The Sing-Off:

Monday night's premiere episode first put all ten groups together for an opening medley of fun.'s hits "Some Nights," "We Are Young" and "Carry On." Tasked to introduce themselves with a signature song – a performance that captures their group's sound and highlights their unique strengths – some groups made a great first impression: the show's first country group, Home Free, championed Florida Georgia Line's "Cruise" (complete with Nelly's verse seductively rapped by the bassist, and as Nick Lachey said, "The bass gets all the ladies!") and a doo-wop rendition of One Direction's "What Makes You Beautiful" by old-timer quartet Street Corner Renaissance.

But some groups didn't represent themselves as well as they might have: All-female group Element fell flat (energy-wise, not musically) with Ellie Goulding's "Burn" failing to convey personality beyond the cookie-cutter identifier of a singing sisterhood with female empowerment (every college has one). Others tried to showcase too much, such as when Puerto Rican fusion group Calle Sol put their microphones down to spotlight their professional dancing abilities instead of supporting their thin arrangement of Rihanna's "Pon de Replay."

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Yet, in the end, it was The Princeton Footnotes' cover of Taylor Swift's "I Knew You Were Trouble" and VoicePlay's performance of Flo Rida and Christina Aguilera's "Feel This Moment" that put the two groups in danger of elimination, saved only by beating the other in an Ultimate Sing-Off – a sudden-death battle (and a new addition from Mark Burnett) that has both groups singing the same track at the same time, leaving the judges to decide who moves forward. While the format had everyone throwing fake punches at each other during the blended cover of 'N Sync's "Bye, Bye, Bye" (instead of touting the song's memorable choreography? How dare they?!), VoicePlay emerged victorious.

Watch the battle below:

Wednesday night put the singers on party patrol, jump-starting the episode with a medley of Black Eyed Peas' "Let's Get It Started," Ke$ha's "Die Young" and Rihanna's "Please Don't Stop the Music." Standouts in the challenge included the performing arts school singers of Vocal Rush on “Gonna Make You Sweat” by C+C Music Factory ("You guys weren't even born when the song was out!" screamed Stockman), and the ’90s-obsessed Filipino boys of The Filharmonic on Montell Jordan's "This Is How We Do It." But the show-stealing performance belonged to Ten, the Dallas-based, gospel-infused collective of professional solo musicians who came together solely to compete on The Sing-Off. They turned up the heat with a male-female duet of Nelly's "Hot in Herre" that overflowed with stage presence and singing techniques reflecting their extensive experience.

While Home Free again delivered, VoicePlay improved, and Element and Street Corner Renaissance skated by (the latter's vocals suffered when coupled with too many dance moves), the scattered performances by University of Kentucky's all-male acoUstiKats of OutKast's "Hey Ya" (complete with actual Polaroid pictures) and Calle Sol of Ricky Martin's "Livin' La Vida Loca" put them against each other in the Ultimate Sing-Off. Battling with Kelly Clarkson's "Stronger (What Doesn't Kill You)," the Puerto Rican performers focused too much on being intimidating within the format, while the college boys slowed the hit to a ballad and brought a new emotional depth the judges hadn't seen before. The creative risk paid off, and the acoUstiKats moved forward.

Watch Ten's heated performance of "Hot in Herre" below:

Thursday night's one-hour episode zoomed in on four groups, first singing Peter Gabriel's "In Your Eyes" together and then being asked to sing a memorable No. 1 hit, under the mentorship of Stockman – another Voice-like element added by Burnett for this season (the panel will rotate throughout upcoming episodes). Ten channeled their gospel roots for an amazing cover of Aretha Franklin's "Chain of Fools," and the acoUstiKats showed off a more sensitive side with Lonestar's "Amazed" – complete with one college student's onstage proposal to his girlfriend in the audience (spoiler: she said yes!).

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Street Corner Renaissance applied their retro sensibilities to Cee Lo Green's "Forget You," complete with a high-pitched wail and humorous asides about the song's swear words. The Filharmonic's genre-bending rendition of  Maroon 5's "One More Night" had Stockman pleased, but left Jewel craving the "sexy anger" of the original track. In a tough night of close competition, these two groups battled on "Na Na Hey Hey Kiss Him Goodbye" by Steam – this time not with distracting faux-aggressive motions toward each other, but side by side, trying to more effectively woo the audience for support, which is a much better indicator of a group's competitive potential. The performance's energy dropped whenever flipping back to the quartet (the con of not beatboxing), and The Filharmonic was saved from elimination.

Watch the acoUstiKats' heartfelt performance below:

The Sing-Off returns for a one-hour episode Monday at 10 p.m. on NBC, and on Wednesday at 8 p.m. for a two-hour jaunt.

What did you think of The Sing-Off's first week? Which groups are flying high and which are falling flat? Sound off in the comments below.

Twitter: @cashleelee