Justin Bieber was one of the many musical guests to make a surprise appearance at Miami's Ultra Music Festival this weekend, where he joined Skrillex and Diplo onstage during their headlining slot.

According to Billboard, Skrillex and Diplo recently came together to form an EDM duo known as Jack U. The two recorded a song called "Where Are U Now," featuring Justin. So when Jack U played it at the festival, it only made sense for Justin to show up and perform it with them. And there Justin was, with little fanfare, taking things a step further than they needed to go by putting his microphone down and dancing a modified Robot onstage. He soon transitioned into punching and kicking the air at random as he jumped around with wild abandon before eventually picking up his microphone and started singing again.

Our favorite part of his performance comes from Justin frantically searching for the microphone he abandoned moments earlier. Check out the video above to get a full picture of what we're talking about.

Justin recently pulled a similar stunt when he joined Ariana Grande onstage during her Miami stop on The Honeymoon Tour, where they performed a duet of Ariana's song "Love Me Harder." Justin messed up part of the lyrics, so they agreed to do a few more songs to make up for it. They sang Justin's "All That Matters" and "As Long as You Love Me" for the crowd, which was so ecstatic they clearly did not care about Justin's lyrical fumble.

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