Sue Gray's report is an utterly damning insight into the heart of power at Westminster

Picture the scene – it's June 2020 and you are working in the heart of Government at a time when indoor gatherings of two or more people are banned.

Families across the country are struggling under strict rules you and your colleague helped to implement.

But instead of following them yourself, you attend a drunken gathering in the Cabinet Office and throw up.

One of the images contained in Sue Gray's partygate report

A karaoke machine is installed in an adjoining office and two other individuals are involved in a "minor altercation".

Hard to believe, isn't it?

There is a danger of becoming numbed to the scale of partygate. The constant drip-feed of damning revelations has led to a kind of scandal-fatigue.

But reading Sue Gray's report, it is genuinely difficult to understand what on earth those involved were thinking.

Was it stupidity or arrogance? Some sort of collective madness?

Vomiting, an “altercation”, excessive boozing, karaoke, red wine stains on walls, a child's swing in the Downing Street garden left broken, staff exiting by the backdoor, a leaving do the night before Prince Philip's funeral in which the last attendee left at 4.20am... It is mind-boggling.

One of the most damning sections is contained in the report's conclusion.

"I was made aware of multiple examples of a lack of respect and poor treatment of security and cleaning staff," Ms Gray writes. "This was unacceptable."

That's one word for it.

Elsewhere, Ms Gray concludes: "The senior leadership at the centre, both political and official, must bear responsibility for this culture.”

Boris Johnson told MPs he was "humbled" and had "learned a lesson". He would make sure the relevant staff apologised to security and cleaning staff.

There is evidence some of those involved knew fine well their behaviour wasn't right. Ms Gray’s report is peppered with revealing WhatsApp messages and emails.

"Just to flag that the press conference will probably be finishing around that time, so helpful if people can be mindful of that as speakers and cameras are leaving, not walking around waving bottles of wine," wrote one special adviser to Martin Reynolds, then the Prime Minister's principal private secretary, ahead of a gathering in the No 10 garden on May 20, 2020.

At the time, the rules only allowed meetings outdoors with one person from another household for exercise or recreation.

"I'm sure it will be fine – and I applaud the gesture – but a 200-odd person invitation for drinks in the garden of No 10 is somewhat of a comms risk in the current environment," noted Lee Cain, then No 10's director of communications, with impressive understatement.

A subsequent WhatsApp message, sent on an unknown date from Mr Reynolds to a special adviser, said "we seem to have got away with" the event.

Meanwhile, one official jokingly referred to a leaving do on June 28 – at which that person above was sick – as "drinks which aren't drinks".

"The event lasted for a number of hours,” Ms Gray writes. “There was excessive alcohol consumption by some individuals.

"One individual was sick. There was a minor altercation between two other individuals.”

Mr Johnson now wants the country to move on.

Whether it does or not is, of course, not up to him.