Season six of "The Voice" is still in full swing, but fans of the vocal showdown are already looking ahead to the next season of the show. That's because in addition to a whole new selection of singers, two new coaches will fill the spinning seats — and bring a bit of magic.
Pharrell: Joining 'Voice' is 'serendipitous, magical'Play Video
Should a dinner party have assigned seats?
Sam Waterson: 'We laugh every day' making 'Grace and Frankie'
Summer Slimdown: See how much weight two viewers lost!
David Alan Grier: I cried backstage after seeing 'Hamilton'
"I just found out about this," Stefani told TODAY's Hoda Kotb, who took the fourth hour of the show to "The Voice" set Monday morning. "I'm tryin' to, like, pinch myself. Is this really happening?"
"It's magical," Williams added.
Actually, it's more than that.
"It's serendipitous," he said. "(Gwen and I have) always had a special connection, and it was always through music that we recognized each other's admiration and depths."
That's because this isn't the first time they've gotten together for memorable, magical music. The two of them co-wrote Stefani's 2005 hit "Hollaback Girl."
"I knew what I wanted," Stefani said of the song. "I described it to him. ... And he's like, 'Oh yeah.' It's like he had it in there already, but he had forgotten about it. He just does his thing. Like, you know, we were jumping on the couch. We knew. ... We knew (it was) magic."
"Yeah," Williams said, agreeing that they saw the hit coming when they wrote it.
Williams knows a thing or two about writing hits — he has a long history of it. He even wrote his current smash, "Happy," but it was intended to be a duet for him and yet another familiar face from "The Voice."
Former "Voice" coach CeeLo Green recorded a version of "Happy" with Williams, but his camp decided it wasn't for him.
"I do regret that it didn't come out because he was so amazing on it," Williams said of the track that went on to become his own solo success. "But I'm not complaining!"
Kotb, who's a self-proclaimed superfan of "The Voice" — and who was clearly happy to hang out on the flashy set — said that she expects Stefani and Williams to "change the whole thing," and she warned that veteran coaches Adam Levine and Blake Shelton "better watch out."
"Your mouth to 'The Voice's' ears," Williams smiled.
"The Voice" airs Mondays and Tuesdays at 8 p.m. on NBC. Season seven of "The Voice" kicks off in the fall.
Follow Ree Hines on Google+.