EXCLUSIVE: Fifth Harmony Teases Surprise-Filled 2017 MTV VMA Performance: 'People Are Gonna Be Gagging!'

The singers will perform their song, 'Down,' on Sunday's awards show.

Get ready for an out-of-this-world Fifth Harmony performance!

ET's Katie Krause chatted with the quartet during the 2017 MTV Video Music Awards rehearsals at The Forum in Los Angeles on Wednesday, where the singers dished on what fans can expect when they take the VMA stage.

"Well, first of all, it's the VMAs. So there's that," Ally Brooke told ET. "Were gonna bring so many different elements and surprises and so much energy. It's really gonna be such a moment and people are gonna be gagging!"

Brooke, Lauren Jauregui, Normani Kordei and Dinah Jane are nominated for three Moonmen this year in the Best Pop Video, Best Choreography and Song of Summer categories for their music video for "Down." The ladies will also be performing the song during Sunday's ceremony.

As far as what their wardrobe will look like when they hit the stage, FH shared that "they don't know yet."

"We really don't know," Jauregui said with the rest of the group echoing her statement.

"It always happens to us," Jane added about waiting until the last minute and also feeling nervous. "Honestly, we were talking about it in the car on our way here."

"But we're gonna be OK," Jauregui chimed in. "We're gonna look fabulous."

"It's gonna be amazing. It's gonna be VMA-zing," joked Brooke.

Fifth Harmony has previously won three MTV VMAs, but what would another win mean to them?

"We've already been blessed with three Moonmen that are in our houses, which is crazy," Jauregui expressed.  "So that feeling, like, anytime you win an award -- but especially these -- they are so iconic. It's just like a humbling experience of like, 'Wow, we worked so hard for this.'"

"And it's so gratifying and, like, validating for somebody to be like, 'Here you go, here's a Moonman,'" she continued. "We're like, 'Wow, thank you.'"

The group will release their third studio album -- and first without Camila Cabello -- on Aug. 25. The singers expressed that they have a special "connection" with their forthcoming self-titled LP, especially after being able to write and record their own songs.

"Being able to connect with the music and just recognizing that you actually believe in what you're doing," Kordei expressed. "I feel like we almost got our power back and we learned to love music again just because, you know, it reflects our voices and we say everything that we wanna be able to say. And we know how we want it to sound and we know that in 10 years it'll mean what it means now to us. It's still special and it's something that we will forever be proud of."

The MTV VMAs air Sunday, Aug. 27 on MTV.

Stay tuned for another Fifth Harmony video tomorrow. For more on the group's new music watch the video below.

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