The lads interrupt Harry Styles' pampering session

Harry StylesOne Direction band mates treated him to a posh massage for his 18th birthday this week – but there was a cruel added twist.

The boys, who were in the US but have now returned home, had been plotting the prank for days.

‘They told the spa manager the plan and while Harry was chilling out, eyes closed, in the relaxation room, the lads ran in with 4 buckets of iced water and drenched him,’ a source tells Daily Star.

After nearly ‘jumping out of his skin’, Harry vowed to get the lads back one day.

It seems practical jokes are a rather regular occurrence when you’re a member of 1D.

‘This lot think it’s funny to come into my room and spray me in the face with a fire extinguisher,’ Niall Horan, 18, told Celebs On Sunday.

‘When I was on the loo, they’d all come in and take pictures of me.’

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Esme Riley