Ten years ago, reviewing Alastair Campbell’s diaries for The Spectator, I concluded as follows:

Who will be the chroniclers of the Cameron government? Somewhere, unknown to his or her colleagues, a secret scribbler will already be at work, documenting the rise and, in due course, no doubt, the fall of this administration.

Well, here it is. It comes from an unpredictable source deep inside that privileged little caste who governed us between 2010 and 2016: Sasha Swire, wife of Hugo, a middle-ranking minister MP for a safe seat in rural Devon and a man who, for all that he was a low-key figure, has a very sharp wit and is fabulously well-connected (he once even walked out with Jerry Hall). The diary covers not only the rise and fall of the Cameroons, but also the shenanigans surrounding Brexit and the inexorable rise of Boris, concluding at the end of last year when Sir Hugo (as he was by then) left parliament.

No holds are barred. Sasha is candid, irreverent, occasionally outrageous and sometimes hilarious. This a world that ordinary mortals, even most Tories, can only glimpse from afar. Hugo — Eton, Sandhurst, Sotheby’s; Sasha — daughter of Mrs Thatcher’s one-time defence secretary, Sir John Knott. Together they have an entrée to all the best salons: Rothchilds, Rothermeres, Rausings, they all feature. There are dinner parties at No. 10, weekends at Chequers, Chevening and Dorney Wood; holidays with the Camerons in Cornwall. Hugo, an upmarket auctioneer by profession, is much in demand at Tory fund-raisers, peppered as they are with obscenely rich oligarchs and (as Sasha calls them) ‘hedgies’. To celebrate his 60th birthday the billionaire Michael Spencer, one-time Tory treasurer, flies a planeload of his ‘besties’ to Marrakesh for ‘an orgy of opulence and bacchanalia’.

An air of entitlement pervades. There is resentment that Sasha’s father is not in the Lords, and that Hugo is not in the cabinet, owing to places having to be found for the much loathed Liberal Democrats and Cameron’s insistence on a quota of ‘over-promoted’ women. There are complaints about the shortage of ministerial cars and references to the need to earn some ‘serious’ money when all this is over. Hugo is contemptuous of the barrow boys on the Tory backbenches (‘most of them are complete tossers’). As for the active members of Hugo’s constituency party, if Sasha is to be believed, they are straight out of some lefty cartoonist’s playbook. ‘They hate in equal measure: foreigners, Europe, defence cuts, gay marriage, liberals, the BBC, Germans, the Japanese, the coalition and garlic.’

There are flashes of self-reflection:

If I was tempted to vote Labour it would be because of social division: the terrible gap between rich and poor. The Labour party still has a modicum of instinct to deal with this whereas…we as a party are…unforgiving of personal circumstances, relentless in telling people to stop whingeing and make a go of it.

Also, much distinctly unwoke banter about sex (Sasha knows what sells). This exchange with the then prime minister on the Cornish coastal path, for example:

‘Don’t walk ahead of me, Sasha.’
‘Why?’
‘Because that scent you are wearing is affecting my pheromones. It makes me want to grab you and push you in the bushes and give you one.’

The Swires’ youngest daughter, Siena, is one of the stars of the show. Aged 13, she fancies herself as a spy, and on the day of a visit by the Queen to Northern Ireland, where her daddy is a minister, makes a note of the top-secret royal programme and details of the security arrangements in a little black book which she then leaves in a pizza restaurant in the centre of Belfast, thereby sparking a huge security flap. Several years later she persuades Hugo to organise a selfie for her with Jeremy Corbyn, who duly obliges, whereupon she shakes his hand and promises to vote for him. ‘Are you really going to vote for him?’, asks Hugo afterwards. ‘Of course not. I was just being polite.’ The girl will go far.

The coming of Brexit is what blows this comfortable little world apart. Out go Dave, George and the rest of the gang. Hugo loses his job in government. In comes the hapless Theresa May and, in due course, Boris. Although no longer in the magic circle, Sasha and Hugo remain acute observers. She is scathing about many of the top brass. Osborne (‘even smugger than usual…up to his megalomaniac tricks again’); Gove (‘toxic’); Gove’s wife, Sarah Vine (‘needs to be under medical supervision’); William Hague (‘only interested in himself’). Jeremy Hunt (‘teacher’s pet’); Boris Johnson (‘longing to be loved’). There is, she says, a Good Boris and a Bad Boris:

Good Boris likes getting rid of regulations, spy satellites, rights-first culture and reverse discrimination…Bad Boris, the Boris we fear, is the casual one. The one who can’t be bothered to read spreadsheets, the one that misses deadlines and the one that makes everything into a joke, the one that trusts everyone and no one…

Hugo stood down at the last election and has now gone off to make some ‘serious’ money. Sasha talks of going to ground at their Devon farmhouse for the foreseeable future. As well she might after this bombshell.