For a fleeting moment it was a flashback to an Old Labour conference at the height of the 1970s.
Barbara Castle's memorial meeting in the Westminster Central Hall was always likely to be one of the diminishingly few flutterings of the Old Labour soul.
And so it was. It had many of the trimmings of the rumbustious annual party rallies she so regularly electrified and, at least once, infuriated.
There was a splash of unfashionable red here and there - even Tony Blair's calculated tie.
Many of the Labour movement's surviving old warhorses - Jack Jones, Rodney Bickerstaffe, Michael Foot - were there to pay their tributes.
The words "comrade" and "socialism" punctuated the proceedings, and even the red roses in the lapels were more a symbol of a county than a party logo.
Union reforms
And, inevitably, there was the prime minister, looking just a trifle out of place, particularly in his attempt to portray the socialist firebrand as a prototype New Labour moderniser.
His speech to the audience of her friends, family, comrades and admirers played heavily on her pragmatism.
And no one needed reminding that her In Place of Strife union reforms saw her defeated by the unions and produced that exceptional conference reception.
At that time, her proposals saw her labelled as a union basher and she was greeted with stony silence at conference.
Equally, none of those who knew her well or worked closely with her were under any illusions about her political beliefs.
It is only in the New Labour world that, in hindsight, she appears like a hard-left champion.
Karl Marx
But most were there to remember the passionate, ideologically-driven fighter for justice and equality - with all her faults.
They were led by former Labour leader Neil Kinnock and, in a performance that many in the Labour movement will cherish, Michael Foot.
For the first time for donkey's years at a Labour meeting - and this is how this event was branded - the names Karl Marx, Beatrice Webb and William Morris were invoked.
In a clear sideswipe at New Labour which Castle would have loved, her former leader and friend reminded the gathering of the imperative of closing the gap between rich and poor, of redistribution of wealth and of keeping the unions on-side.
He even revived memories of the 1970s "socialist incomes policy", which, he said, could point the way to the future.
He ended simply: "Those of us who knew her the best loved her the most."
Red Flag
Her former aide during her time in the European parliament, Jack Straw, paid his tribute as did friends Glenys Kinnock and Gordon Brown.
In one of many anecdotes about her, the Chancellor recalled how he was invited to her 90th birthday party and said he would be delighted to go if she promised not to attack him over pensions at the next conference.
"She agreed. I went to the party and she spoke at the party conference," he said.
All remembered her great achievements - the equal pay act, seat belts, the breathalyser, child benefit and the state earnings related pension scheme.
She would have been delighted at the small pensioner demonstration outside the event declaring her battle for pensioner rights, on their behalf, would not be abandoned.
She would undoubtedly have allowed herself a small, immodest smile at the unveiling of a new bronze bust of her, commissioned by the Commons works of art committee.
And she would most definitely have enjoyed the video clips of her past performances, which punctuated the proceedings.
They even played the Red Flag - on video of course, not sung live - and ended with the socialist anthem Jerusalem.
The only thing missing at the end was a card vote.