The power of the image. Or four of them, to be precise.
Just when the prime minister might have hoped the bumpy moments of Partygate might be beginning to ease, these pictures emerge.
He's raising a glass. He's holding forth. There's a table festooned with wine bottles, and what looks like a bottle of hand sanitiser.
We already knew about the event in question.
Until today, though, we'd not seen pictures from it or known for certain that at least one person there was fined, but the prime minister was not.
There's one thing knowing about a party, something else seeing pictures from it. Pictures of partying when the rest of the country was in lockdown.
The Liberal Democrats are now demanding to know how Boris Johnson escaped a fine for being at a do at least one fellow attendee was fined for being at.
The big question, though, is how much does it matter? How many minds will move, particularly among Conservative MPs who, remember, have the capacity to remove a party leader if they choose?
'Government not serious'
Let's be clear: Very few Tory MPs will find looking at these pictures comfortable. Very few will hurtle enthusiastically towards TV cameras to defend them.
Backbencher Steve Baker archly tweeted a public health poster from the time. A patient is being helped to breathe. 'Look her in the eyes. And tell her you never bend the rules.'
Fellow Conservative MP Tom Tugendhat told the BBC he hopes "very much that people will be considering how they act" in the coming days when asked whether it was time for a change of leadership.
"I think those pictures show, I'm afraid, what many of us have known for a long time - which is that some aspects of this government are not serious," he said.
To which aspects could he be possibly be referring?
But I'm not sure in and of themselves these pictures will magnify the mellow to the mega-aggrieved on the Tory frontbench or backbenches.
I'm not sure it'll turn a Tory MP irritated, even angry, at their boss's behaviour into one now determined to topple him.
And plenty remain loyal.
"I think colleagues are finding it all very tedious and don't think it will affect Boris any more," one cabinet minister told me, adding that the prime minister had been "unfairly treated" and "will survive".
There is, though, the report from the senior civil servant Sue Gray to come, with some in government anticipating receiving it on Wednesday morning, before a statement from Mr Johnson after Prime Minister's Questions at lunchtime.
And after that will come a parliamentary inquiry into whether he intentionally misled the Commons — something he denies.
Any prime minister would prefer to not have days like this, but as things stand, the point of most pressing imminent danger to Mr Johnson over Covid rule-breaking does seem to have passed.
But the long-term consequences of this stream of revelations - on perceptions of his trust, integrity and believability - will be exploited by his opponents for years to come.