This past week, Justin Bieber broke some hearts and raised some red flags when he cancelled a string of high profile performances and appearances, including The Late Show With Stephen Colbert and a performance at the Macy's Thanksgiving Day Parade. Many were concerned that he might be sick or going through something very personal in his life. Just days after the performance cancellations, however, the pop star turned up at the Shrine in Los Angeles for a surprise performance at The Chainsmokers' concert.

TMZ reports that the Friday November 27 performance was pretty impromptu, with Bieber crashing the stage (with The Chainsmokers' blessing) to perform three of his current hits including "Where Are U Now" and "Sorry." Check out some fan-filmed footage below:

Despite the artist's other cancellations, it looks like The Biebs was in high spirits and enjoyed himself during the last-minute surprise set, hanging out with the EDM act as well as actor Ansel Elgort and photographer/director/"professional life liver" Rory Kramer backstage. (Kramer also directed Bieber's Purpose video for "I'll Show You.")

After the performance, Bieber addressed the sold-out audience, thanking his buddies The Chainsmokers for allowing him on stage and telling the crowd of five thousand what an "honor" it was to be there perform with them. He also continued to gush on Instagram, sharing, "Thank you to The Chainsmokers. You guys put on a hell of a show and [I was] honored to be a part of it."

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