Silversun Pickups with their fill-in bassist Sarah Negahdari of the Happy Hollows in Irvine, California on May 18th, 2013. 

Surprise guests for the evening, Stone Temple Pilots perform with their new frontman, Chester Bennington, in Irvine, California on May 18th, 2013.

The Black Keys closing out 2013’s KROQ Weenie Roast in Irvine, California on May 18th, 2013.

Vampire Weekend onstage and dancing the night away in Irvine, California on May 18th, 2013. 

Of Monsters and Men climb trees before their set in Irvine, California on May 18th, 2013. 

Aubert Brian of Silversun Pickups on the mic in Irvine, California on May 18th, 2013.

Jimmy Eat World playing hit after hit in Irvine, California on May 18th, 2013. 

"Hey!" Of Monsters and Men perform their hit single "Little Talks" in Irvine, California on May 18th, 2013.

Fitz and the Tantrums hang by their bus in Irvine, California on May 18th, 2013. 

Keith and Michael Jeffery of Atlas Genius performing in the golden sun of Irvine, California on May 18th, 2013.

Capital Cities waiting to head to the stage in Irvine, California on May 18th, 2013. 

Imagine Dragons’ Dan Reynolds performed despite a broken wrist in Irvine, California on May 18th, 2013.

New Politics frontman David Boyd taking a break from singing duties to breakdance in Irvine, California on May 18th, 2013.

AWOLnation enjoying themselves by their bus in Irvine, California on May 18th, 2013. 

Tyler Joseph of Twenty One Pilots was one of many artists performing for fans during KROQ's 21st Annual Weenie Roast in Irvine, California on May 18th, 2013.

Brothers Keith and Michael of Atlas Genius hanging out in their trailer in Irvine, California on May 18th, 2013. 

AWOLnation’s Aaron Bruno at KROQ’s Weenie Roast in Irvine, California on May 18th, 2013.

Twenty One Pilots backstage in their bus in Irvine, California on May 18th, 2013. 

New Politics showing off their moves backstage in Irvine, California on May 18th, 2013.