Is this is the moment "Spreadsheet Phil" finally breaks out of his cell?

Bar a political miracle, the chancellor's transformation from bookish numbers man to rebel leader will be complete on Wednesday.

Striding out of cabinet before he can be sacked, Mr Hammond will deny Boris Johnson the satisfaction of axing someone seen by many as the bogeyman of Brexit.

Image: Philip Hammond (R) is striding out of cabinet before Boris Johnson can sack him

But has this really been the political metamorphosis many make out?

Mr Hammond's parliamentary private secretary, the Conservative MP Huw Merriman, said it is the political context that's changed - not the chancellor.


"He's very consistent. He's got a set of principles that are core to him… making sure the economy is not damaged," he explained.

Mr Merriman, who remained an aide to the chancellor despite speaking out in favour of another public Brexit vote, said the increasing prominence of no deal has caused Mr Hammond to act.

"If you've been managing the economy for a number of years, and you see that being put at risk by ideology, you're going to have deep, deep concerns," he added.

The Sussex MP denies his boss is the grey character many make out - and claims Mr Hammond actually has a "dry sense of humour" and is "great company".

A look back at some of Mr Hammond's recent budgets show a penchant for a joke or two, even if they are of the dad variety.

Go back further still, and there is more evidence that an inner rebel has always been lurking under the dry appearance.

A memorable Newsnight interview with TV presenter and classmate Richard Madeley revealed Mr Hammond was a "goth" while at school who paraded around in a "leather trench coat with The Guardian under his arm".

Asked about those claims, the chancellor sought to set the record straight, saying it was "probably the Financial Times, not The Guardian".

But even if Mr Hammond has stayed more consistent than many realise over the years, the controversy around him has ratcheted up as the Brexit saga intensifies.

For those on the eurosceptic wing of the party, he is the ultimate "establishment remoaner". The Eeyore of the Treasury, obsessed with pessimistic financial forecasts, dismissive of the opportunities of Brexit.

Image: Philip Hammond is a staunch opponent of a no-deal Brexit

"Good riddance," texts one Conservative council leader, who had been wavering between Jeremy Hunt and Boris Johnson before eventually plumping for the latter.

"He's dreadful and boring. As chancellor he never seemed to think any new thoughts - continuation, cautious Osborne," he added.

That is a view you hear among some entrepreneurs and business folk as well, who paint a picture of a chancellor pushing bland policies that look sensible on paper but fail to land well in the real world.

It may be that the increasing hostility of late has fired up this reluctant rebel.

Loyal and respectful of the conventions of government, there is little doubt that - when liberated from cabinet - he will be a key figure in the emerging rebel alliance of MPs against a no-deal Brexit.

"He's got steel, he's got conviction... he has great leadership qualities which will now be seen outside of cabinet," Mr Merriman said.

"Just watch him, his best times are to come."