On Aug. 19, 2014, "America's Got Talent" (AGT) Season 9 (2014) kick started the final week of four-part Quarterfinals round, where in another 12 performers performed to impress the public. Howie Mandel, Howard Stern, Mel B and Heidi Klum continue to be the part of the show as judges and mentors to the contestants. Here is a detailed recap of what happened on "America's Got talent" (AGT) Season 9 (2014) Quarterfinals-Part 4. Read on to find out the details about the performance episode. [Warning: Spoilers Alert!]

This article contains spoilers from "America's Got Talent" (AGT) Season 9 (2014) Quarter Finals- Part 4. Read only if you want to learn more about it.

Last week viewers enjoyed some very entertaining acts. Even the judges said it was an amazing night on the show. The show followed the same format wherein, four out of 12 acts were selected to advance in the semifinals on the basis of public votes. One act gained entry as judges' choice. The five semifinalists selected last week are: Sons of Serendip, Blue Journey, Paul Leti, Christian Stoinev and Acro Army.

The acts performed on the first night of "America's Got Talent" (AGT) Season 9 (2014) Quarterfinals Week 4 were: Dom the Bom's Triple threat, Smoothini, One-Voice Children's Choir, Extreme Dance Company, Emil and Dariel, Nina Burri, Quintavious Johnson, Bad Boys of Ballet, Kelli Glover, Mothmen Dance and Jonah Smith.

The show kick started with the performance by Bad Boys of Ballet. The group performed on the song "Problem" by Ariana Grande. While the female judges gave them a standing ovation, the male judges suggested them to bring variety in their routine.

Next was One-Voice Children's Choir. They sang hit movie "Frozen's" song named "Let It Go." The group got mixed reviews by the four judges.

Jonah Smith, the pianist took over the stage next and performed "Stay With Me" by Sam Smith. The judges appreciated his performance and Howie Mandel said that the singer was "the best performer of the night so far."

Dom the Bom's Triple Threat performed some tricks with cards. The group of children received mixed judgments from the judges. Heidi said that the act is fun to watch but doesn't portray illustrate good behaviour. Howard felt that their act is difficult to perform, but they could have presented it in a better manner.

Extreme Dance Company took the stage next and performed a dance routine. Heidi Klum said they were great, while Mel B felt the performance was dated. As for Howie, the group oozed out passion for dancing and Howard said they were good but won't be remembered by the audience.

The next act was by Emil and Dariel, the cellists' duo. All the judges seemed very impressed. Howie said they always surprised them. Howard felt they are unforgettable. As for Hiedi Klum and Mel B, they gave them a standing ovation.

Nina Burri, the contortionist, took the stage next. She performed an act that impressed all the judges. Howard said she performed beautifully. Heid felt she was great and Mel B said she was mesmerized by her performance. Howie Mandel said she is very talented and sexy.

Next up was Quintavious Johnson. The 12-year-old singer sang "And I Am Telling You" and earns generous praises by the judges. It was the first time on "America's Got Talent" 2014 Quarterfinals Part 4 when all the four judges stood up together. The judges felt that the child is incredibly talented with powerful voice.

Mothem Dance troupe set the stage on fire with the mix of dance and acrobatics performed in front of spectacular and artistic backdrops. Their innovative style seemed to impress all the judges. However, Mel B felt it was some sort of a repetition. At the same time, Howard felt they were fun to watch. Heidi feels they rely too much on the video playing in the background.

Smoothini, the magician from Dominican Republic was next performing. He did some magic tricks with dollar bills and seemed to impress Mel B the most. Howie felt that they were amazing. However, he failed to leave an impression on Heidi Klum and Howard Stern.

Smoothini was followed by Jonatan Riquelme. The hand balancer performed a balancing act on rola bola boards. His act left everyone nervous. But he impressed all the four judges with his daring performance.

The last to perform on "America's Got Talent" (AGT) Season 9 Quarterfinals Week 4 was Kelli Glover. She sang "If I Ain't Got You" by Alicia Keys. Heidi and Howie Mandel felt she was great. However, Howard and Mel B felt she needed to be more confident.

"America's Got Talent" (AGT) Season 9 (2014) Quarter Finals Week 4 will continue on Wednesday night with elimination episode. Don't forget to tune into NBC at 9 p.m. EST.

For more spoilers and recap of "America's Got Talent" (AGT) Season 9 (2014) Quarter Finals, read below:

America's Got Talent (AGT) Season 9 (2014) Quarter Finals- Part 3 Recap, Spoilers: Cornell Bhangra, Acro Army And More Outshined

'America's Got Talent' (AGT) Season 9 (2014) Quarter Finals Week 3 Results Recap, Spoilers: Top 5 Acts Enter Semifinals