It's no secret that One Direction love to play pranks on each another.
Louis Tomlinson, 20, recently 'fessed to Now's Dan Wootton that he yanked 18-year-old Niall Horan's trousers down at a service station - and we've got the video to prove it!
Luckily for you, a keen-eyed 1D fan caught the hilarious moment on camera and posted the clip on YouTube for all the world to see.
What do you reckon the Irish cutie should do to get his revenge - whip his pal's pants down on stage, maybe?
Check out Louis' prank on an unsuspecting Niall below...
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