In the early hours of Friday morning, the Prime Minister was delivered a defeat on a scale not even the most optimistic of Liberal Democrats would have predicted.
The statistics will drop from the lips of supporters and activists like windfall fruit. A 34 per cent swing, the seventh biggest in history. A Conservative majority of nearly 23,000 is now a 5,925 majority for Helen Morgan MP.
I am still processing the magnitude even though I was there. Part of it. I had knocked doors in North Shropshire. Heard the anger and frustration of so many people who had voted Conservative in good faith but now felt ignored and taken for granted by a government reneging on promise after promise.
Even so, when party officials called me over to outline the victory I was about to claim in the media I was momentarily speechless.
A seat that the Conservatives had held for almost two centuries, their 58th safest, had voted Liberal Democrat, and done so by a comfortable margin.
A by-election result can often tell us which way the national wind is blowing. It is universally acknowledged that it is typically harder for the party of government, whoever that may be, to hold a seat mid-term.
But what we saw last week was a result which we may look back on as one of those watershed moments for a Prime Minister certainly, and perhaps British politics.
Nearly two years into the pandemic – where many of us feel we are no further forward than we were at the start and this Conservative government is making little progress with the mounting crises we face – there is now a glimmer of hope.
Across the country, people can now believe that change can actually happen, not just because of this one by election but because of the trend they see emerging.
Six months ago, a similarly unlikely victory was seized by the Liberal Democrats in Chesham and Amersham.
The swing there was slightly less than Friday but still considerably more than would be needed to snatch previously safe Conservative seats where they were second in 2019, and change the shape of the next government.
That is why North Shropshire and Chesham and Amersham create such a powerful narrative. They are a representation of the actual change which many long for.
Those voters, abandoning Boris Johnson’s party in their droves, reflect the frustration of millions whose patience with the blind fop’s failure to provide leadership in the pandemic has long expired.
In Scotland, we have felt it acutely. It has also been used by those who would tear our family of nations apart to provide false evidence for their case. As if one Prime Minister, a temporary resident of the office, should be enough to reject all that has worked, and still works so well for us.
In the pandemic more than ever, we have needed the combined strength of our Union to meet the economic and health challenges it has posed.
What we all saw on Friday morning is that the frustration and anger is not a Scottish preserve, as the separatists would have us believe.
It is now clear that the previous darling of the right is no longer the favoured son of our family in the South.
It is the way that he has led his party’s approach to the current series of crises which is at the root of the dissatisfaction which now permeates not just Conservative constituencies but the parliamentary party itself.
Last week around 100 of his MPs voted against Johnson’s most recent proposals, his plan B for tackling Covid.
Many more have expressed reservations in private conversations.
What they, as a party, had yet to acknowledge, was the dissatisfaction that people on the doorsteps in North Shropshire were expressing with his approach to the economy, to the growing cost of living crisis, the increase in inflation, and the still-mounting pressure on NHS services and staff.
The final straw for many was that party – or should that be parties – in Downing Street. The lack of respect for the suffering faced by so many felt like a collective slap in the face.
The voters’ response was to turn to the Liberal Democrats for a fairer deal where everyone plays by the same rules. To a politician who has already proven she is prepared to listen to the people of North Shropshire and work for them.
To a party which wants a better deal for businesses struggling with the burdens created by the pandemic and for families struggling to cope with rocketing fuel costs and inflation this winter.
I have no doubt on Friday morning that Conservative MPs with majorities less impressive that the previous one in North Shropshire were already looking over their shoulders.
And that in Conservative offices, answers were already being sought to the conundrum they now face. Is the party over for Boris? Is it time to try a different way?
On Friday it seemed senior party figures were still willing to give him one more try with influential 1922 Committee representatives expressing it in US baseball speak of two strikes down, one more and he could be out.
The voters of North Shropshire have delivered their verdict in much clearer language. The future not just of this Conservative government, but if us all, may depend on how his party responds to their message.
Christine Jardine is the Scottish Liberal Democrat MP for Edinburgh West