What a difference a day makes. Gordon Brown has had another personality change. Only the day before, at Downing Street, he was confiding how shy he was. “I am a shy person,” he told us in a voice as soft as a kitten’s fur. Contrast that with Mr Brown yesterday at PMQs — a shouting, ranting bull of a man, steam snorting out of nostrils. We seem to be in a Jekyll and Hyde situation, updated for politics and renamed Heckle and Shy.

I blame David Cameron, who triggered it all by dangling in front of the PM the red rag that is the record youth unemployment figures. “You once promised to abolish youth unemployment,” taunted Dave. “Do you accept that you’ve failed?”

The PM struggled to stay shy. He tried to keep his voice low and steady. He told us, voice expanding by the word, about his wonderful programmes to get youngsters into work. As he boasted, Cabinet ministers began to nod. First David Miliband bobbed his head up and down like one of those dogs on the back shelves of cars. Then Alan Johnson succumbed. Soon the entire front bench had been infected by the Incredible Nodding Virus. The PM looked at them, shyly of course, and seemed pleased.

But Dr Heckle was lurking for all to see. Voice rising, he accused Dave of being against employing young people. Labour MPs egged him on, cheering wildly and, yes, heckling. The PM told Dave that the youth unemployment figures weren’t accurate because one quarter of those youngsters were full-time students looking for part-time work. “They are not fully unemployed,” he shouted, as if this made anything any better.

Labour lout Chris Ruane boomed out: “Dodgy figures Dave!” Screaming Labour MPs pointed at the Tories who screamed even more and pointed back. MPs were loving it. They seemed to have forgotten that the figures represent real people. Normally the Prime Minister would say, in his shy voice, how much he feels the pain of the unemployed. But not yesterday. He was shouting too much for all that mushy stuff.

“I think the Prime Minister is living in a parallel universe!” shouted Dave, exasperated. Did the PM accept that he had failed? Gordon lunged at the despatch box. “NO!”

That was the last we saw of any hint of Mr Shy. The Prime Minister was like a man possessed. You could see that he was furious (he had yet to admit that even one young person was unemployed) and began jabbing his finger into the dispatch box until I feared for his knuckle. This was bare-knuckle shouting.

Dave brandished a leaked memo, saying that it held details of future cuts, including fewer apprenticeships. “Doesn’t this leaked memo show that you are planning cuts?” he demanded, savouring the C-word that caused so much angst earlier this year.

Gordon raged: “Every time we mention policy, you lose it!” Dave raged right back, looking at the baying Labour MPs and crying: “They know they have a party leader who’s LOST it!” He demanded again that Gordon acknowledge that he is planning cuts.

The mention once again of the C-word was too much for the Prime Minister. He denied it all. He wasn’t cutting apprenticeships but increasing them! He ended by shouting the word “WRONG” half a dozen times at Dave. I have to say that, for a shy person, it was pretty wild.

Annus Horribilis by Ann Treneman is published by Gibson Square at £9.99. To order at £7.99, postage free, call The Times bookshop on 0845-271 2134.

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