Justin Bieber is the King of Pranks and when someone pranks him, he's going to get them back good… and Willow Smith learned this the hard way. "so the other day @officialwillow decided to try and prank me. PRANK ME!! lol. well now is PHASE 1 of my REVENGE!! Manchester get ready!!" Justin wrote on his Twitter right before he pulled the ultimate prank on the "Whip My Hair" singer.

SEE IT: Justin Bieber's wax figure

At Justin and Willow's concert in Manchester, England on Sunday, Justin, Jaden Smith, Justin's manager Scooter Braun, and Justin's swagger coach Ryan Good took whipping their hair to a whole new level when they surprised Willow on stage wearing crazy wigs. Justin even brought out his cowbell. Take a look:

https://www.youtube.com/watch?v=D9esptZhQfQ

Do you think Justin's prank was funny? What would you have done if you were Willow?

Photo: Courtesy of Carin Morris' Twitter

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