Justin Bieber, One Direction's Niall Horan and Cody Simpson hosted their own jam session over the weekend, and their respective fandoms reacted in a frenzy.

The three blond heartthrobs spent Sunday night together hanging out with some friends, instruments in tow. A Snapchat video posted by one of the three was shared via Twitter on fan accounts, featuring Bieber crooning "Home to Mama."

The buds also snapped selfies with fans during their night out, sending hundreds of thousands of fans into shock and admiration.

Sunday night, Simpson shared a photo of himself posing with the 1D member, Bieber and Corey Harper on Instagram.