She is known as Harriet Harperson and her fan club has never been big. But yesterday, before PMQs, it seemed positively tiny. Harriet arrived on the front bench a bit early, sitting so calmly that she might have been petrified. She was surrounded by men in suits, almost all of whom thought she would fail and that they could do better anyway. All the women in the Cabinet were there but no big Brownites had made the arduous journey.

“Questions to the Prime Minister!” cried the Speaker.

“Where’s your stab jacket?” shouted a Tory.

“I have been asked to reply,” said Harriet in her precise way, every word distinct, as orderly as a soldiers’ formation.

William Hague popped up. He gets £15,000 per after-dinner speech. I am not sure how much Harriet earns, if anything. Indeed, she might have to pay them to let her speak.

I feared what was to come. Every week I watch Harriet “perform” as Leader of the House with her Shadow, Theresa May. Harriet refuses to do what she calls “Judy and Judy” politics. Her style is Stakhanovite: doggedly and, indeed, sometimes heroically workmanlike. Jokes are a foreign country. She needed to raise her game to the stars now.

“I would like to congratulate the Leader of the House for being the first female Labour member ever to answer PMQs,” Mr Hague said to a distinctly muted cheer. “She must be proud three decades on to follow in the footsteps of Margaret Thatcher!”

Maggie got a bigger cheer. Harriet smiled, apple cheeks glowing. Perhaps she had left her hair shirt at home with her stab jacket. “I thank him for his congratulations,” she said. “But I would ask him, why is he asking the questions today? Because he is NOT the Shadow Leader of the House. She is sitting next to him.”

MPs cheered. Theresa May, famous for her footwear and in patent leather over-the-knee boots yesterday, did not join in. But Harriet wasn’t done. “Is this the situation in the modern Conservative Party that women should be seen but not heard? [More cheers] If I may, perhaps I could offer her a bit of sisterly advice. She should not let him get away with it!”

MPs were shouting “More! More!” Harriet may never have heard this before. Certainly I never have for her.

Mr Hague, sounding rather hurt, said that he had planned on being nice to Harriet. “She has had a difficult week,” he said. “She had to explain that she dresses in accordance with wherever she goes. Presumably when she attends Cabinet, she dresses as a clown.”

This got a laugh, I know not why. Harriet is not a clown, she is a worker-bee and now she was buzzing.

“If I am looking for advice on what to wear or what not to wear,” she said, “I think the very last person I would look to for advice is the man in the baseball cap.” A joke! A real honest to goodness Harriet joke! The chamber rocked with laughter. It was impossible to look at Mr Hague now without seeing that ridiculous cap perched on his egg head. He had lost this match now - Harriet held her own on the subject of the economy - but he still had one more go, trying to embarrass her about something she had written in her blog.

“I wrote that blog as part of my Harriet in the High Street listening scheme,” she piped, bursting into laughter at how ridiculous this sounded, the Pippi Longstocking of politics.

The chamber laughed with her, not at her. In the gallery, her husband, Jack Dromey, the Labour Party treasurer, beamed. Against all odds, Harriet the Harridan had become Hattie the heroine, at least for one day.

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