They came in their tens of thousands. From the length and breadth of Britain, protesters headed for Manchester to speak with one voice in defence of the National Health Service.
And there is no doubt that the Tories heard - they were gathered in the city for their annual conference.
Not that they dared show their faces as the streets filled with union banners, protest placards and the thunder of drums, piercing sounds of whistles and angry chants.
Some estimates put the number of demonstrators at over 50,000.
They were in Manchester to protest against the destruction and privatisation of the NHS by the Tories and their Lib Dem collaborators.
The demonstration took place as firefighters, teachers, postal staff, and other public-sector workers prepare to fight in defence of their services, their jobs, pensions and working conditions in coming weeks.
The growing mood of resistance was fully in evidence. The march wound through the streets for three hours. At its head was public-service union Unison, a contingent which was itself thousands strong.
They marched off 20 abreast, filling Manchester's main thoroughfare Deansgate.
The banners showed the spread of support and of anger - from Edinburgh, Tower Hamlets, Glasgow, Northern Ireland, Kensington and Chelsea, Solihull, Leeds, Birmingham, on and on they came.
Among the marchers were Danielle and Stuart Marns-McClure with their three-year-old son Finn in a pushchair. The family had travelled over from Calder Valley in West Yorkshire.
"I am objecting to the destruction and privatisation of the health service," said Danielle. "And the Tory Party in general and everything they stand for.
"I am a student nurse. I'm working on the wards so I know what it's like - borrowing staff from one ward to cover another."
For hours the marchers filed into Whitworth Park in Manchester for a rousing rally.
Speaker after speaker tore into the coalition. The roars of approval were deafening.
TUC general secretary Frances O'Grady said the NHS in England faced the "gravest crisis in its history."
She said: "The government is wasting billions implementing reforms nobody wants and nobody voted for.
"Our NHS is not for sale, not today, not tomorrow, not ever."
Unison general secretary Dave Prentis predicted a return to the "bad old days when if you had money you had good health, but if you were poor you did not.
"Make no mistake, privatisation will suck money out of the NHS.
"It will suck money out of patient care. It will cut wages. It will cut corners. Patients will suffer."
When the profits weren't enough, he warned, the spectre of charges would appear.
Unite union leader Len McCluskey accused David Cameron of "lying" about the NHS.
"Our ambulance service is now under threat. Pathology services are being sold off.
"Queues in most A&E departments are amounting to 12 hours, with sick people being treated in corridors.
"Hospital after hospital are chronically understaffed, with wards shutting - as winter looms we are heading for the biggest crisis to face the NHS for a generation.
"I say to private healthcare, you had better not get too comfortable - for this is our NHS and we will take it back."