NBC's reality talent show "America's Got Talent" (AGT) Season 9 (2014) has reached its semifinals round. The show kicked off its round one of two-part semifinals on Aug. 26. 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) Semifinals Round 1-Day 1. [Warning: Spoilers Alert!]

This article contains spoilers from "America's Got Talent" (AGT) Season 9 (2014) Semifinals Round 1-Day 1. Read only if you want to learn more about it.

Previously, viewers enjoyed quarterfinals round wherein top 20/semifinalists were selected out of top 48 performers. The results were based on public voting. Additional four acts were selected on the basis of judges' choice.

"America's Got Talent" (AGT) Season 9 (2014) Semifinals Round kicked off with 12 acts performing. The acts that set the stage on fire in round one were: Sons of Serendip, Mike Super, Miguel Dakota, Mara Justine, Flight Crew Jump Rope, Emily West, David & Leeman, Dan Naturman, Bad Boys of Ballet, Aerial Animation and Andrey Moraru. Guest star of the semifinals round one was pop diva and teen sensation Ariana Grande.

The show kicked off with the performance of by a wild card entry, Flight Crew Jump Rope. They performed lots of tricks to the song "Break Free" by Ariana Grande. While Mel B and Heidi seemed impressed by their talent, Howie Mandel and Howard Stern felt they were not perfect and were repetitive.

Next up on the stage was Mara Justine. She sang "Breakaway" by Kelly Clarkson and all the four judges liked her.

Mara was followed by Bad Boys of Ballet. They performed on on "Are You Gonna Go My Way" by Lenny Kravtiz. The judges praised their talent and said they are great dancers. Howie Mandel feels they could be great backup dancers.

Paul Leti, the singer, took the stage next. He sang "I Want it That Way" by Backstreet Boys. This was not Paul's best performance and Heidi Klum pointed that out. Howie Mandel said that Mara Justine performed a lot better than him and Howard noted that he was having a tough time with the song

Mike Super performed next. He made the judges shuffle the card and then did some tricks. He performed without Desmond this time. His act impressed the judges and Howie said that he could win $1 million. The other judges appreciated his tricks.

Andrey Moraru, the extreme hand balancer, performed some tricks. He managed to impress all the four judges who loved his act.

Miguel Dakota was next. The singer and guitarist performed "Seven Nation Army" by The White Stripes and dedicated it to his grandparents. Howard thinks that he is talented but there is something missing. Meanwhile, Heidi thinks he could be a sensation in America. Howie thinks that he could win the show.

Sons of Serendip the band performed next. They sang "Don't You Worry Child." Howie and Heidi stood up for the band's performance. Heidi thinks they will get through to finals. Mel B felt their performance was beautiful and Howie said they are really talented.

Next was a performance by David & Leeman. The two magicians presented some magic tricks and they garnered mixed reviews from the judges. While Howie liked it, Mel felt there is an information overload. Heidi loves the way they present the act.

Next was Dan Naturman the comedian. Heidi wasn't too impressed by his jokes, but Mel, Howard and Howie think he is funny.

Next was Aerial Animation. Abigail the Aerial Animator told a story through her acrobatics skills. Her semifinals performance failed to impress all the judges. Mel was not so happy with her act and Heidi thinks that this wasn't her best performance. Meanwhile, Howard and Howie praised her and think she is an incredible performer.

Last to perform on "America's Got Talent" (AGT) Season 9 (2014) Semifinals Round 1 performance episode was Emily West. She performed "Who Wants to Live Forever" by Queen. All the judges loved her performance and Howard Stern thinks she is worthy of winning $1 million prize.

"America's Got Talent" (AGT) Season 9 (2014) will return with Semifinals Round 1 Elimination Episode on Wednesday, Aug. 27, 2014. Don't forget to tune into NBC.

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

'America's Got Talent' (AGT) Season 9 (2014) Quarterfinals Week 4 Results Recap, Spoilers: 5 Semifinalists Revealed

'America's Got Talent' (AGT) Season 9 (2014) Quarterfinals-Part 4 Performance Episode Recap, Spoilers: The Child Singer Outperforms All

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