In the teaser, Willoughby can be seen sitting on a throne-like seat while seemingly being interviewed.
After spotting the presenter in the scene, a detective asks: “Is that the queen of daytime?”, to which his colleague replies: “Gloria Hunniford? Are you sure?”
After the scene was played, GMB host Richard Madeley exclaimed: “That’s Holly!” while Kate Garraway added: "What’s she doing cropping up in Midsomer?” before they interviewed star of the show, Neil Dudgeon.
Dudgeon, who plays DCI John Barnaby in the ITV drama series, responded: “Well, she’s sort of a friend of the show I suppose – she’s a great fan of the show and we’re always looking to broaden our casting net.”
Discussing Willoughby’s cameo further, which was filmed two years ago, he added: “She was great, she was thoroughly professional.
“I think she was a bit nervous when she first arrived. She’s playing a character called Holly Willoughby, I wouldn’t like to say that it’s herself.”
This isn’t the first time she has appeared up on the show, with the Dancing on Ice star previously making a cameo back in 2021.
At the time, she described her cameo as one of the best days of her life, with the star’s friends and family rushing to praise her once the episode aired.
Discussing her appearance on This Morning back in 2021, she shared: “Everybody I know who has watched all of Midsomer says it’s one of their favourites we’ve ever made.
“I said to them: ‘Thanks for having me, it was one of the best days of my life’.”
She also revealed to her then co-host Phillip Schofield that it took her almost 25 takes before she was able to deliver her scripted words out properly.
Willoughby admitted: “It wasn’t ‘take one’, put it that way... Or ‘take two’ or ‘take 10’. Around about take 25 I got the words out but it’s fine.”