The fourth round of "The Voice" blind auditions was underway last night as the four coaches pushed their buttons and tried to pursue talented unknown artists to be on their teams. There were some standout contestants last night, but none as impressive as twins Andi and Alex.

From the very first note out of the 23-year-old twins' mouthes, they were completely in sync. They sung a slowed down folk version of "Thank You" by Dido. Andi and Alex were just as strong singling solo as they were when they nailed the harmonies together. Seconds into the girls audition, Gwen Stefani and Adam Levine turned around, followed later by Blake Shelton and Pharrell Williams.

"Are you guys sisters?" Levine asked the girls.

"We're twins," they said at the exact same time.

Levine told the girls he would "fight for them as hard as I can" and Shelton reminded them that he took a duo, The Swon Brothers, to the finals in season four. In the end the twins picked Team Adam.

In addition to Andi and Alex, there were multiple other incredible auditions last night. Viktor Kiraly came all the way from Budapest, Hungry, to audition for "The Voice."

Kiraly chose "What's Going On" by Donny Hathaway and nailed the song with his soulful and controlled voice. Levine turned around almost immediately, followed later by Shelton.

After Kiraly hit a couple of perfect-sounding high notes, Williams and Stefani both turned around at the same time and gave the singer a four-chair turnaround. All four judges once again put up a solid fight to have Kiraly on their team, but in the end he chose Team Adam.

The most impressive solo woman of the night was Krista Hughes from Coal City, W. Va. The small-town country girl gave an absolutely incredible performance of "Angel From Montgomery" by Bonnie Raitt.

Hughes had one of the more unique voices of the night and completely wowed all four judges. Levine turned around before Hughes even finished the first line of the song. Seconds later, the other three judges turned around and watched the country singer do her thing. Levine, Williams and Stefani all gave Hughes compelling reasons why she should choose them over Shelton, but Shelton made a very good point to Hughes.

"Song choice for you may be more important than any other artist that's going to audition," Shelton told Hughes. "You need somebody who can get there with you, so please pick me as your coach."

Hughes could not ignore Shelton's point and chose Team Blake for her home on "The Voice."

The last notable person to audition on night four of "The Voice" was Darius Scott. Scott tackled Usher's breakthrough hit "You Make Me Wanna" and nailed every single note. As soon as the groove of the song picked up, Levine turned around, followed by Williams and Stefani. Scott's audition only got better and better.

The only judge that did not turn around for Scott was country artist Shelton. The fight between Levine, Stefani and Williams was the most entertaining ones of the night. Stefani pointed out that she had the most experience and the longest career in music while Levine promised he would fight for him. As a lifelong N.E.R.D. fan with a tattoo of the band on his body, he chose Team Pharrell.

After night four of "The Voice" blind auditions, all four coaches have ten contestants on their team. Team Pharrell added two new singers as did Team Gwen and Team Blake. Levine did well last night and added four new artists to his team including the incredible duo of Andi and Alex who already look like front runners.

"The Voice" returns next Monday at 8 p.m. ET on NBC.