Strictly Come Dancing star John Sergeant treads the wards in Casualty this Saturday.

The former political reporter plays a political reporter covering the story of sick ex-Labour MP, Margaret Sampson (Ann Mitchell). Having spent a couple of weeks in and out of the Emergency Department, Margaret suffers a heart attack in this week’s episode. John guests as a story-hungry journalist, waiting outside the hospital with the rest of the press.

John, 65, made his TV debut back in 1966 in a six-part comedy sketch show, On The Margin, alongside Alan Bennett. These days he’s a regular on the broadcast circuit, often appearing on Have I Got News For You and Countdown. He also hosts his own comedy debating programme, Argumental, on Dave.

“John has plenty of experience of being on TV, but always appeared as himself, not pretending to be a different person,” a source close to the star reportedly said.

“Obviously he’s nervous about his first acting job, but he will be drawing on his experience in front of the camera to help him prepare for the role.”

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