Kemi Badenoch brought shock tactics to Prime Minister's Questions which won her death glares from Labour MPs. The Tory leader suggested Sir Keir Starmer should ask why Labour backbenchers say they are being called members of the "paedo defenders party".

For a few seconds the divisions in the Labour party melted away as hundreds of stunned MPs stared at her with undisguised loathing. British democracy is famed for robust debate but the Commons was awash in weapons-grade toxicity.

The trigger for Mrs Badenoch bringing up that a Labour MP had been "arrested for child sex offences" was Sir Keir joking that the only change she had brought to her party was to "make it smaller" - a nod to the recent spate of defections to Reform UK.

Nobody ever asks if the PM and Mrs Badenoch get on together behind the scenes. Each looks at the other as if they are a mosquito they yearn to swat.

Dressed in a dark enough outfit to turn up at a funeral, Mrs Badenoch declared: "The defining moment of this man's premiership will not be breakfast clubs. It will be the sight of the man he appointed as ambassador to Washington just last year getting arrested."

Sir Keir described her as "utterly irrelevant". Labour and the Conservatives together command the support of just over one in three of the electorate, but the PM and the Tory leader's common mission to steer their parties away from oblivion has not won fostered any mutual respect.

She devoted most of her questions to student loans, challenging him to cut interest rates. But Sir Keir arrived in the Commons determined to do last minute electioneering ahead of Thursday's Gorton and Denton by-election, in which Labour is in a three-way fight with Reform and the Greens.

He accused Nigel Farage of having "neither the decency nor the backbone to condemn a death threat". This was a reference to the deputy leader of Lancashire County Council sharing an online message saying a Labour MP "should be shot" - an act for which he has apologised.

And he blasted the Reform candidate in the by-election for being a force of "hatred and division" before attacking the Greens. He claimed the party wanted to change the law so his son could buy "heroin and crack cocaine" in a few months time when he turns 18.

Roberta Metsola, the president of the European Parliament, was one of the VIP guests in the chamber. After watching around 40 minutes of insults and accusations flung between the parties she might well have thought: "Thank goodness this lot aren't in the EU any more."