Believe it or not, it's been 10 years since Gwen Stefani and Pharrell collaborated for the first time to create the pop smash 'Hollaback Girl.' Now they're reuniting for the equally upbeat track 'Spark the Fire.'

The two released a snippet of the visuals for the song on 'The Ellen DeGeneres Show' Monday (Nov. 24). The clip shows an intense party atmosphere and the No Doubt frontwoman dancing in the middle of a crowd.

Pharrell, dressed in a black T-shirt and rocking his signature 'Happy' hat, bops around while playing some imaginary drums. There's also animated captions used to show some of the lyrics.

Since joining the cast of the 'The Voice' as coaches, it only made sense for the megastars to work together again. Plus, 'Hollaback Girl' was the first No. 1 record for Stefani on the U.S. Billboard Hot 100 Charts, so it's clearly in her best interest to reconnect with arguably the hottest producer of the moment.

After showing the clip, Ellen announced the full video will debut in a week. Stefani's next solo album will drop in December, though few details have been shared about the concept, the title or even a specific release date. 'Spark the Fire' will appear on the effort.

As far as Pharrell, he'll be quite busy next month doing a string of dates for the pop concert Jingle Ball. On Dec. 5, he'll be at the Staples Center in Los Angeles. Then the following day, he'll head to Rosemont, Ill., and after that, Madison Square Garden in New York City on Dec. 12. You can see the full list of the singer's Jingle Ball dates here.

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