Stephen Mulhern bursts onto 'This Morning' to tease Ant and Dec prank

Holly Willoughby and Phillip Schofield’s mysterious behaviour on This Morning this week seems to have been cleared up, with more evidence that Ant and Dec had a hand in it.

Viewers suspected Willoughby and Schofield were taking part in the Geordie duo’s Saturday Night Takeaway I’m A Celebrity, Get Out Of Me Ear segment when they acted oddly during a cooking segment.

Watch: Was Lorraine Kelly doing the Ant and Dec earpiece challenge? Viewers think so

And the plot thickened on Thursday, when Ant and Dec’s Saturday Night Takeaway co-star Stephen Mulhern burst onto the set of This Morning and announced that the show had won some sort of prize.

Read more: Phillip Schofield told to 'shut up' as he quizzes Jim Carter on This Morning

"Stop what you are doing!" he shouted. “Let me tell you, I bring good news.

"This Morning, you are the winners of On Air Dares."

Handing over a trophy as confetti fell from the ceiling, Mulhern teased: “All will be revealed this Saturday on Saturday Night Takeaway.”

As Willoughby and Schofield celebrated their mystery win, Mulhern rushed out as quickly as he had entered.

This Morning viewers had been suspicious during a cooking demo with chef James Martin, when Willoughby asked whether it was true that shiitake mushroom powder should be used in choux buns.

She also began trying to walk off a cramp in her leg, and struggled to talk with her mouth full of bun.

And Willoughby and Schofield weren’t the only presenters exhibiting some odd behaviour this week.

Remarks made by Lorraine Kelly during an interview with KSI on ITV's Lorraine left viewers thinking she was also taking part in Ant and Dec’s game, which sees them control famous people's chats by giving them instructions via an earpiece.

During her talk with the rapper, the TV star repeatedly yawned, mentioned a mouse being on the loose and flapped at her face, complaining that there was a fly in the studio.

She also said she had cramp and tried to walk it off, just like Willoughby did.

Read more: Holly Willoughby stunned by offer of Midsomer Murders role

Acknowledging it had been a strange morning, Kelly later told fans that "all will become clear in the fullness of time".

Ant and Dec’s Saturday Night Takeaway airs at 7pm on ITV on Saturday.

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