Philip Schofield got revenge on a kid who swore on telly - by handing out his number and prank calling him for days.
His co-presenter Sarah Greene on Going Live was left red-faced when a foul-mouthed teen let rip during an interview with pop group 5 Star.
Philip revealed: "I was listening to the studio in my earpiece and Sarah was taking questions for the band.
"Eliot, who was about 16, came on the phone to ask one. There was a dog barking in the background, identified as Tammy.
"‘Do you have a question for 5 Star?' asked Sarah. ‘Yes, I'd like to ask them why they're so f****** crap,' said Eliot.
"‘Right,' replied Sarah calmly. ‘I'm sure Tammy would have made a lot more sense. Let's move on to line three. Do you have a sensible question?'
"As calmly as it was handled on air, we were all affronted.
"You couldn't call in without giving your number and being called back, so we had his number.
"It was handed out to a few people and for a few days we dialled the number and hung up.
"Gentle revenge was very satisfying as we occasionally got him out of bed and, better still, he didn't know who it was."
In his new book Life's What You Make It, Philip also admitted that he was banned from borrowing teddies for the CBBC Broom Cupboard from classic kids show Play School - after placing them in sexual positions.
Philip, 58, added: "The only show we ever upset was Play School. In an act of extreme trust, they sent over their legendary character toys from the programme – it was as if royalty had arrived.
"In a carefully carried box were Big Ted, Little Ted, Humpty, Jemima and Hamble. We used them that afternoon.
"Unfortunately, the runner arrived earlier than expected to our office to collect them and was met by a very disturbing sight.
"I had arranged the toys for the amusement of Ian (Stubbs, his producer).
"Big Ted was 69ing Hamble while Little Ted, Humpty and Jemima were involved in a passionate threesome.
"The runner was not amused, and they were never allowed to visit us again."