Ariana Grande had another surprise for the crowd at Coachella!

After she brought NSYNC on stage for her first weekend, she had a treat for beliebers this weekend!

While she was performing at her headlining gig, Justin Bieber returned to the stage after TWO YEARS!
Bieber performed his hit "Sorry" with Ariana and said to the audience: "I had no idea I was going to be on a stage tonight. Absolutely no idea. I wore this fly outfit not knowing I was going to be on stage."