The magic number is 54. This is how many Tory MPs have to write a secret letter to the chairman of their 1922 Committee in order to trigger a vote of no confidence in Boris Johnson. There are easily more than 54 Conservative MPs who think their leader is a busted flush, who appreciate the risk his attempts to hang on to the premiership will inflict lasting reputational damage on their party and who understand that Britain won’t return to anything resembling seemly and orderly government until he is gone. One senior Tory ended a conversation with me by quoting François Rabelais: “Bring down the curtain, the farce is over.” Quite a lot share the public revulsion with the lockdown-busting of the prime minister and his staff. Some agree that he lied to MPs and that it is critical to the integrity of our politics that deliberately misleading parliament is always treated as a resignation offence. More are agitated about what leaving Mr Johnson in place means for their electoral prospects. All can read the opinion polls. His personal ratings have plunged to depths not even plumbed by Theresa May at her lowest point. This strongly suggests we are witnessing the implosion of the Cult of Johnson that I wrote about at the time of the last Tory party conference. And yet Sir Graham Brady, the man who keeps count of the letters, has not announced that the magic number has been reached. Tory MPs scheme, gossip, brief, speculate and plot. With a few exceptions, what they have not done is act. One of the exceptions is David Davis, the prominent Brexiter and former cabinet minister. He waited until Prime Minister’s Questions had gone into injury time before he rose to confront the prime minister by quoting Leo Amery quoting Oliver Cromwell. “In the name of God, go.” Things would be much easier for Tories if their leader took that advice and walked away. That would spare everyone the spectacle of ministers tortuously trying to defend the indefensible. His departure would probably reduce the chances of more Tories following the example of Christian Wakeford, the Bury South MP who defected to Labour. A swift exit is not the outcome desired by Labour, which is best served by weeks more of dreadful headlines for the Tories, accompanied by poisonous infighting among them. So you can see why some Conservative MPs are attracted to the notion that their leader might be induced to announce that he is off to spend more time with his families. Mr Johnson’s friends have often heard him whingeing that he can’t live on the salary while moaning that being prime minister is not as much fun as he thought it would be. It never seems to have occurred to him that making money and having a laugh are not the top lines of the job description. On the retelling of Dominic Cummings, his former boon companion turned enemy, Mr Johnson was bored with being prime minister within a month of the 2019 election. “This job,” he groaned. “It’s like getting up every morning pulling a 747 down the runway.” Even as a disgraced ex-prime minister, a lucrative afterlife would await him as a celebrity speaker. He could return to writing columns for the Telegraph, a much more appropriate vocation for him than heading a government. He could finish his long-delayed book, Shakespeare: The Riddle of Genius. He could then pen his memoirs, which he has the ego to entitle Johnson: The Wronged Genius. To go now might earn him a bit of redemption with his party, and possibly even with some of the public, for eventually doing the decent thing. You probably choked as hard reading that last sentence as I did writing it. Anyone acquainted with his biography knows how unfamiliar he is with the concept of doing the decent thing. Putting the interests of others before his own is alien to a man who has always been governed entirely by his ambitions and appetites. His remaining allies are busy briefing friendly journalists that he will fight to stay in Number 10 to the bitter end. They would say that, of course. They hope to deter Tory MPs from moving against him by filling them with terror that prising him out will be a grisly enterprise with no guarantee of success. One former cabinet minister predicts: “Boris will only be dragged out of Number 10 with his fingernails clinging to the door. There will be scratch marks down the woodwork.” The battle to save his skin has already turned vicious. From William Wragg, a Tory committee chairman who was once a keen supporter of the prime minister, we have heard charges that blackmail is being used against MPs suspected of wanting him gone. Mr Wragg thinks this is another scandal and one grave enough to merit investigation by the police. Westminster has always been associated with dark arts and dirty tricks, but intimidating MPs by threatening to cut off government funding for schools or hospitals in their constituencies takes things to a previously unvisited and atrocious level. That is government by extortion racket. Another sign of Mr Johnson’s desperation is “Operation Save Big Dog”, the puerile appellation apparently invented by himself to describe the effort to buy him more time. The attempt to pander to rightwing Tories by throwing them lumps of “red meat” included spinning a yarn that asylum seekers could be sent to Ghana. The government of the west African country exposed that as fiction by ridiculing it as “Operation Dead Meat”. There is no step too low for Mr Johnson, including trashing Britain’s international reputation. The longer Tory MPs prevaricate, the more they become complicit in this scandal and the less the public will trust the lot of them. They surely know this. So what is stopping them? One scenario haunting the Conservative benches is that a confidence vote is triggered in the next few weeks, Mr Johnson just scrapes through and then insists he has a right to carry on. They would then be stuck with a leader who was finished, but not finished off. That prompts some Tories to seek reasons to delay the moment when they reckon with the mistake their party made when it gave him the premiership in the first place. I hear some Conservative MPs arguing that he should be given a period of “probation” to see whether he can put together a more professional team at Number 10 and run a better government. That’s like having Dracula before you and a stake to hand, but offering him three months to prove that he can be a vegetarian. Then there are those dithering Tory MPs who contend that they should put the decision in the hands of the voters by waiting for the May elections. One Conservative MP reports that his local councillors are angrily demanding: “Why should we be sacrificed because Tory MPs lack a spine?” The most common mantra on the Tory benches is “wait for Sue Gray”. The bulk of them have fallen in behind the idea that they should pause until the senior civil servant has concluded her investigation into the parties scandal. The Johnson loyalists are hoping that Ms Gray will grant him some kind of reprieve by widely spreading culpability for the rule-breaking booze-ups at Number 10. Even before Ms Gray had completed her interviews, the prime minister’s propagandists were putting it about that her report would exonerate him from the most damning charges. That’s a dangerous game for Number 10 to be playing, not least because Ms Gray will have a strong regard for her own credibility. Someone who knows her well remarks: “She will be very pissed off by that.” Some of the Tory MPs who want him gone, but have yet to say so into a microphone, are indicating that they are waiting for the release of the report before they add their voices to those calling for his resignation. Ms Gray’s findings are now expected to be published this week, later than originally planned. That’s because she has uncovered more evidence about Number 10’s party culture as she has gone along. The prime minister has committed himself to being questioned about it by MPs, who should insist that the report is published in full. Ms Gray is a civil servant, not an independent prosecutor or judge. Her findings, and the degree of severity with which she chooses to word them, can tip the scales for or against the prime minister with Tory MPs, but ultimately they will have to make the decision. Those who want rid of Boris Johnson will have to be as resolute about evicting him as he is frantic to cling on. Andrew Rawnsley is Chief Political Commentator of the Observer