Katy Perry was one of the artists who took part in Ariana Grande's "One Love Manchester" concert earlier this month and she just shares some behind-the-scenes video from the historic concert.
Stars like Ariana Grande, Justin Bieber, Miley Cyrus, Niall Horan, Coldplay's Chris Martin and Mac Miller all turned up in the video, which also feature footage of Katy's rehearsal and performance of "Part of Me."
Source: Katy Perry