Coachella 2019 has been the year of the surprise guest drop-in.

On weekend one, Selena Gomez popped up at DJ Snake’s set with Cardi B and Ozuna, and then on weekend two Will Smith blew up the internet when he joined his son Jaden Smith on-stage.

On the last night of the music festival in Indio, California, Justin Bieber sent the crowd wild when he appeared on stage during Ariana Grande’s set.

Bieber explained the drop-in wasn’t planned. He realised he needed to warm up, as it were, since it’s been years since he performed live – so he gave Ariana a call.

“I had no idea I was gonna be on a stage tonight, absolutely no idea,” he told the thousands in the crowd, with Ariana confirming “true story.”

“So anyways, this is my first time onstage in like two years,” Bieber said.

“I had to get my groove back, I had to get my swag back, you know what I’m saying? Thank you so much, Coachella, thank you so much, Ariana Grande.”

The 25-year-old, whose wife Hailey Baldwin was in the crowd, launched into a rendition of Sorry with Ariana joining in.

He finished off by announcing “By the way, album coming soon.”

People on Twitter have accused Bieber of lip-synching. So what if he was? The guy hasn’t sung publicly in two years. Can we just let him live? #LetJustinLive