Shakira, who welcomed a son, Milan, in January, and Usher officially took over for Cee Lo Green and Christina Aguilera Monday night, joining Blake Shelton and Adam Levine on the show's two-hour season 4 premiere.
The quartet kicked off the show with a group performance of the Beatles' "Come Together," with Levine on drums and Shakira playing a harmonica while Shelton and Usher traded licks on guitars.
But it was the emotional backstories of several contestants that stole the show.
Kris Thomas, a pastor's son who signed a record deal and lost it after college, recounted a story of nearly driving his car into a house while intoxicated. His gender-bending falsetto on Whitney Houston's "Saving All My Love for You" shocked the judges who didn't realize a man was on stage until they turned their chairs to face the R&B singer.
"In my four seasons, I've never heard anything like that," Levine said with surprise.
"You're a gem," said Shakira, who claimed him for her team.
Danielle Bradbery, 16, of Cypress, Texas, wowed the judges with her performance of Taylor Swift's "Mean." Later, Usher attempted to bribe her with Justin Bieber tickets but Danielle ended up with Shelton.
"What the hell? This is crazy," he said when she told him it had been her first big performance.
In the end, however, it was Judith Hill of Pasadena, Calif., who wowed The Voice's coaches and audience the most. Levine and Usher turned around in their chairs before Hill finished the first few lines of Aguilera's "What a Girl Wants."
Her soulful rendition of the song left Shakira with her mouth gaping open and Levine standing atop his chair cheering.
"You are the first person who has ever come on this show and done a Christina song as well as Christina Aguilera," Levine said.
"I'm going to light myself on fire," Levine continued as he begged to be her coach.
"It's like a star just hatched out of a shell up there," Shelton said.
"My heart is beating fast right now because I really feel I am in front of a star," Shakira said as the judges fought for Hill.
Eventually, she picked Levine.
Blind auditions continue Tuesday on The Voice.