Fifth Harmony's Britney Spears Cover Is A Giant 'Oops': Watch It Now!

'X Factor' contestants take on Spears' iconic '... Baby One More Time' during a karaoke party with MTV News.

"X Factor" underdogs Fifth Harmony may have shocked viewers when they made it into the finale, but since then, have certainly proved the doubters wrong.

Since signing with mentor Simon Cowell's Syco label, the girl group — composed of Dinah-Jane Hansen, Lauren Jauregui, Normani Hamilton, Camila Cabello and Ally Brooke — saw their lead single, "Miss Movin' On," peak at #1 on the U.S. iTunes charts.

During their time on the "X Factor," they covered songs from all artists, including Demi Lovato and Ellie Goulding, which is why MTV News decided to enjoy an afternoon of karaoke in New York City. Watch the video to see the girls in action!

The bubbly fivesome said their go-to karaoke songs include Destiny's Child's "Say My Name" and JoJo's "Too Little Too Late," but after combing through thousands of songs, they decided on Britney Spears' iconic "... Baby One More Time."

Yet, before the quintet showed off their vocal skills, they sat down to discuss their new uptempo pop single, "Me and My Girls," which they co-wrote.

"What's so cool about that song is girl party songs are all about going out and meeting boys," Cabello said. "We are like, 'No, we are going to stay in our pajamas, we are gonna eat some pizza.' "

Fifth Harmony, who admitted to being a little nervous for their upcoming album, have enlisted some of music's top producers, including Julian Bunetta who has worked with One Direction, to help put together a debut.

"It's a variation, we talk about different things and different sounds," Lauren said of the album. "But we get to show the range of our vocals in each of the songs."

Not only do they want to show off their musical capabilities, but they also want to craft songs that their avid fans, who call themselves harmonizers, can relate to.

"We want to share with our audience and our harmonizers that we are five girls," Lauren said. "And we are not perfect and you don't have to be perfect. We want everybody to believe in themselves."

Next up for Fifth Harmony, they are hitting the road next month with another "X Factor" alum, Cher Lloyd, for the I Wish Tour.