The One Direction guys are notorious pranksters, which is why we're a little surprised that it has taken this long for them to pull a prank on stage during their Where We Are tour. Naturally, Harry Styles was the victim of the joke (isn't he always?) — Liam came up behind the curly haired cutie and totally startled him, causing him to jump out of his skin and then hold the railing in front of him for support.
The 1D guys are always joking around with each other. Click through to see 10 times they've been involved in pranks, then let us know which one you find the funniest in the comments below.