Whether you admire or loathe Dominic Cummings, think he's credible or dishonorable, his testimony on Wednesday was remarkable.
For such a senior advisor to so openly and comprehensively try to demolish a sitting prime minister and his top team was jaw-dropping.
But put aside your feelings for the witness and his motives, what is undeniable is the impact of his testimony as he told the public they had been failed by this government. If you boil down the hours of evidence he offered, it comes down to this: "Tens of thousands of people who died didn't need to die."
There was no smoking gun in Mr Cummings' seven hours of evidence - although that may come later when he provides written evidence to back up some of his eye-popping claims to the committee. Instead the former right-hand man to Boris Johnson painted a picture of a deeply dysfunctional, chaotic government led by a prime minister ill-prepared to deal with a pandemic for which the public paid a deadly price.
He put on record what Number 10 and the prime minister have for months sought to stonewall as the government kicked the beginning of the public inquiry into the COVID pandemic into 2022.
The UK was woefully unprepared for the pandemic; failed to grasp the nettle in February and early March; came to the first lockdown too late; failed the public by releasing people into care homes without being tested; had a border policy that exacerbated difficulties in controlling the disease; was too late to lockdown in the autumn.
He also put on record that he did not think Mr Johnson was a fit and proper person to be prime minister and lead the country through this pandemic. Again the public may already have a low view of Mr Cummings after the Durham debacle, but for the person who was so closely aligned to Mr Johnson to not just publicly disavow him but also place the blame for thousands of deaths directly as this door was disturbing.
From the two-week holiday in February, to the glib assertion that the coronavirus was like "swine flu" and the repeated policy U-turns or appetite for chaos, Mr Cummings exacted a series of personal blows on the prime minister designed to bring into question Mr Johnson's competence and character.
But most damning in the evidence wasn't the personal attacks, but the criticism of the policy (or lack of it) that led to loss of life. For me the sharp intake of breath moments came when Mr Cummings relayed the moment on 13 March when the former Deputy Cabinet Secretary Helen McNamara came to Number 10 to warn of the disaster that was about to unfold.
"I've been told for years there's a whole plan for this - there is no plan," Mr Cummings claimed Ms McNamara said. "I've come through here to tell you I think we are absolutely f**ked." Mr Cummings said the government realised it needed to lockdown, but didn't have a plan for how to do it.
And then on care homes, his testimony was devastating. "The whole rhetoric was 'we put a shield around care homes'. The opposite happened, rather than put a shield around them we send people with COVID into care homes," Mr Cummings said as he recounted one of the most horrific and haunting policy failures of the pandemic that cost so many people their lives. For this, he blamed Matt Hancock, who he said he asked to be sacked "on an almost daily basis".
Finally, on the second lockdown, Mr Cummings was excoriating of a prime minister who he said never wanted a first lockdown and was cross with him for pressing a second. Mr Cummings claims that as he and the PM's scientific advisors pressed for a circuit break in late September, the prime minister dug in.
"Surely we've got to learn the lessons of the past? The PM decided no, and basically said we'd sit and hope." By the time the PM triggered the second lockdown on 31 October, relations between the two men were "essentially finished".
Mr Cummings told the committee that he wished he'd done more to force the prime minister into an earlier autumn lockdown. "What I ought to have done [after the meeting on 22 September when PM refused a two week circuit break] is said I am resigning in 48 hours. If you take serious action, I will leave and go quietly. If you don't, I will call a press conference and say the PM is going to make a terrible decision and it's going to kill thousands of people."
And tens of thousands of people did die over the winter into the spring. There were over 50,000 COVID deaths from the beginning of March 2020 to early November. In the subsequent seven months, through the second and third lockdowns another 78,000 people have died.
Number 10 may hope that the witness, unpopular with the public, has already discredited himself, and can be cast as an egomaniac intent on revenge. But the accusations he has levelled at the government can't be simply dismissed.
Mr Johnson gave Mr Cummings access to the inner rooms of Number 10 and that means his testimony counts. And however uncomfortable that evidence session was for Mr Johnson, it was far worse for those watching who have lost loved ones over the past year.
The prime minister will no doubt deflect away from this (in the words of one MP) "car crash" testimony, by referencing the public inquiry he intends to hold next year.
But Mr Cummings on Wednesday put on record the first draft of history in the government's handling of the COVID-19 crisis and it makes very bad reading for Mr Johnson's leadership and legacy.