When Psy appeared on stage wearing a white tuxedo, the crowd went wild. Psy began his performance by screaming out "Scream!" and created a club-like atmosphere which hyped up the people in the audience.
Everybody in the crowd was busy doing the horse riding dance with Psy and capturing videos of his performance of "Gangnam Style."
'iHeartRadio Music Festival' is hosted by Ryan Seacrest, whom Psy met a couple of days earlier when he was a guest on Ryan Seacrest's radio program. During the meeting for the radio show, Ryan Seacrest had asked Psy to go to Las Vegas for the music festival.
Today, the festival will continue in Las Vegas with global stars like Rihanna, Usher, Taylor Swift, Bon Jovi, and Green Day.