LOOK: PENTATONIX Surprises KATY PERRY With "Chained To The Rhythm" Performance

American a capella group Pentatonix suprised Katy Perry during the "Swish Swish" singer's Witness livestream that occurred for more than 72 hours inside her Big Brother-inspired house. 

In the video, Katy Perry is seen sitting on her makeup chair when three of Pentatonix's members appeared in her room and started singing "Chained To The Rhythm" in harmony. Katy - bewildered by their sudden emergence - sang along with the group and hugged them right after they finished singing the song off her fifth studio album. Watch the video below: 

Video courtesy: Katy Perry

What can you say about Pentatonix's suprise performance of "Chained To The Rhythm"? Feel free to leave us a comment!