Oh those naughty boys
Celebrating his birthday in the USA, Hazza got a bit more than jelly and ice cream - or should we say jell-o and frozen yoghurt - from the rest of the 1D lads.
As a Hollywood source told the Daily Star: "Harry's bandmates were mischeviously plotting something for his birthday for days.
"They asked the hotel staff at the W hotel for ideas and toyed with booking a really large, hairy man to give him a special birthday massage."
That sounds more like Zayn's kind of nightmare, we all know how he feels about hairy nipples.
In the end, the band did treat him to a massage, but clearly they couldn't find anyone hairy enough and opted to surprise him with an icy gift half-way through instead!
"They told the spa manager the plan and while Harry was chilling out, eyes closed in the relaxation room, the lads ran in with four buckets of iced water and drenched him."
Although he took the joke well, Hazza has vowed to get the boys back and we can't wait to hear what he's got up his sleeve.
Not content with prank calling Simon Cowell, the 1D boys clearly aren't lacking in imagination when it comes to practical jokes.
As Niall told Celebs On Sunday: "This lot think it's funny to come into my room and spray me in the face with a fire extinguisher. When I was on the loo, they'd all come in and take pictures of me."
Oh, to get our mits on that camera.
If you were Harry, how would you get the other lads back?