Nadine Dorries writing book about downfall of Boris Johnson

Former Culture Secretary Nadine Dorries is writing a book about the political downfall of former PM Boris Johnson.

Mr Johnson was forced to quit in July by the resignation of dozens of his ministers after a series of scandals.

One of the first to go was then-Chancellor Rishi Sunak, whom some Conservative MPs accused of betraying the prime minister.

Ms Dorries' literary agent told the BBC the book would be published next autumn and its working title was The Plot.

He said she had already begun writing it.

He described it as "a political whodunnit: murder on the Downing Street express".

Those "who want to know whose fingerprints are on the knife will have to buy the book", he added.

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A former nurse, born in Liverpool, the MP for Mid Bedfordshire is already a successful author of romantic historical novels set in Liverpool and Ireland.

During the Conservative leadership contest, which followed Mr Johnson's resignation, she was repeatedly critical of Mr Sunak, accusing him of leading a "ruthless coup".

When Mr Sunak resigned as chancellor, he blamed divisions over economic policy and the government's integrity.

He lost the contest to Liz Truss, but then replaced her when she quit just over six weeks later amid the economic and political turmoil which followed the September mini-budget.

Mr Johnson had indicated he would run in a leadership contest, opening the way to a return to Downing Street, but pulled out, clearing the way for Mr Sunak to take over.

Boris Johnson and Nadine Dorries promote rural broadband days before he was ejected as PM

Despite her criticisms of Mr Sunak, the Evening Standard reported that Ms Dorries was playing down suggestions her book would point the finger at the new prime minister for forcing Mr Johnson out.

She has frequently argued Mr Johnson is the only Tory leader who can beat Labour at the next general election.

She recently told The House magazine: "He will be back. I don't know when, I don't know how, I don't know whether it will be 10 years or 10 months."

Ms Dorries is thought to have been nominated for a peerage in Mr Johnson's resignation honours list, though her appointment is believed to have been delayed to avoid triggering a by-election.

Conservative MP Julian Knight, who chairs the digital, culture, media and sport select committee, told the Evening Standard: "I'm sure the book may give Rishi some sleepless nights. Nadine is not known for her forgiving streak, and I imagine she won't pull any punches when naming names and pointing the finger.

"It's all part of a thread of covert asides at the new regime… you have a rump of Johnsonites and then those sacked by Liz Truss. There's a lot of discontented people around."