Dermot O'Leary was forced to change his outfit on Friday's This Morning after getting covered in cream.
The 48-year-old TV presenter was interviewing Chris Tarrant on the ITV show alongside Alison Hammond when he found himself speechless.
In a nod to Chris's former children's television show Tiswas, a Phantom Flan Flinger suddenly crept onto the set and slammed a pie into the side of Dermot's face.
Alison, 47, immediately burst out laughing as the person dressed all in black quickly ran off.
Chris, 75, carried on speaking about Tiswas (Today Is Saturday: Watch And Smile) as if nothing had happened and said: "I don't really miss it at all because I used to sit there covered in custard."
"Still got it, Tarrant!" Dermot shouted with one eye closed.
"Oh my goodness! I can't believe they used to do this all the time," Alison remarked as Chris confirmed: "All the time!"
Turning back to Dermot, mother-of-one Alison told him: "Babes, you are covered in it!"
"It's really quite nice actually," Dermot responded as he licked some of the custard off of his hands.
"It's only your old jumper and old trousers, you're alright," Chris said, before adding: "Look at the state of you!"
Viewers tuning in at home thought it was hilarious and claimed that Dermot was actually 'fuming' after the prank.
"Low key fuming ain’t you Dermot#ThisMorning," one person tweeted.
Another posted: "Dermot pretending to love the joke when he’s secretly FURIOUS! #ThisMorning."
A third viewer said: "So @thismorning best clip of the week??? @radioleary being [pie emoji] by the #phantom … just what I needed to see to cheer up a rubbish week… literally laughed out loud!! @AlisonHammond #thismorning."
This Morning airs weekdays at 10am on ITV and ITV Hub.