An exuberant Angela Rayner was all smiles as she welcomed her old friend Andy Burnham into her constituency home, confident the so-called secret summit would not stay private for long.

She wasn’t disappointed. Within 48 hours of their meeting two Fridays ago, a photograph appeared on a tabloid front page of Burnham, the Labour mayor of Greater Manchester, outside the four-bedroom detached house in Ashton-under-Lyne, having arrived in his gleaming new silver Mercedes.

As befits a so-called man of the people, he drove himself. Some reports suggested that he arrived in disguise, complete with an odd-looking hat. ‘Not so,’ I’m assured by one of the mayor’s supporters. ‘It was a trick of a camera. He was hatless.’

The meeting, about the deepening crisis in the Labour leadership, came only days after Burnham and Rayner were photographed with Sir Keir Starmer at a school in Greater Manchester. They looked like one big happy Labour family. ‘But what were they really thinking in that shot?’ asked one Labour MP.

For the plot took another twist two days ago when it emerged that MPs are demanding Starmer lines up Burnham as his successor as Labour braces for a battering in the local elections. The idea is that Starmer could set a timetable for his departure, giving Burnham, 56, enough time to find a seat.

But Rayner, 46, who was forced to quit the Cabinet last September after failing to pay £40,000 stamp duty on an £800,000 seaside flat which she bought in Hove four months earlier, has one very good reason to continue plotting her own coronation.

I have heard from several sources that she has come close to an agreement with HMRC after its lengthy investigation over the unpaid tax, something she expects to be confirmed publicly – possibly as early as this week. ‘She is over the moon,’ says a trusted source.

If she is ordered to pay a fine, she expects it to be for a minor technical infringement – certainly not grave enough in her mind to rule her out of a leadership bid.

She has a short memory and, it seems, a tendency towards hypocrisy. In April 2022, it was Rayner who led calls for the then Prime Minister Boris Johnson and his Chancellor Rishi Sunak to quit after they were each fined £50 for a minor breach of the Covid lockdown rules. Rayner tweeted: ‘You made the rules. You broke your own law. Just go.’

But that was then and this is now. While she once considered a minor fine to be a career-ending setback, today Rayner and her supporters don’t see her HMRC misdemeanour as any impediment to challenging Starmer’s leadership after next month’s local election results, which are expected to be catastrophic for Labour. ‘It sounds like it’s a technicality, so she can go for it,’ declared one supporter.

Whether she would be clear in the court of public opinion is another matter. The investigation into the stamp duty affair by the Prime Minister’s ethics adviser, Sir Laurie Magnus, concluded Rayner ‘cannot be considered to have met the highest standards of proper conduct as envisaged by the [Ministerial] Code’.

And yet her popularity in the Party means she has strength in numbers – which is handy. To mount a bid for leadership she will need the backing of 81 MPs, a fifth of the parliamentary party.

Team Rayner is split on the wisdom of an immediate challenge. While some say fortune favours the brave and she should seize the initiative; others argue she should wait for a stalking horse candidate to mortally wound Starmer. ‘She must not wield the knife,’ says one supportive MP, who cites the fact that those who have in the past often fall themselves.

But what unites all her supporters is the firm conviction that Rayner is a Prime Minister in waiting. Which represents a remarkable turnaround for a woman who, as little as nine months ago, was in despair over her political future after resigning as deputy PM and Housing Secretary over the stamp duty row.

For years, she denied she was interested in running for leader. Now she thinks about little else. I am told by several sources that there’s one major reason for her change of heart: her boyfriend Sam Tarry. The couple have been in a tempestuous on-off relationship since he helped run her deputy Labour leadership campaign six years ago. While he has been separated from Julia Fozard, the mother of his two children, I can disclose they have now divorced.

His and Rayner’s relationship hasn’t been plain sailing either. They went through a brief separation in 2023, but now appear to be very much on.

And that should be a grave concern to Mail on Sunday readers given we are talking about a potential future Prime Minister. Because to describe Tarry as a socialist firebrand would be to underplay just how Left-wing he is.

A member of the extreme Socialist Campaign Group, which wants to nationalise the ‘commanding heights’ of the economy, he ran Jeremy Corbyn’s successful leadership campaign in 2016. Now he believes he can work the same magic with Rayner.

As one senior figure told me: ‘Tarry has persuaded her she can and should be leader.’

One very telling indication of the strength of their relationship is that she bought the Hove flat so Tarry, 43, would have a base close to the home of his former wife and their two children. Another senior MP told me: ‘Ange is in the mess over her tax affairs because of the Hove flat, which she bought because of Sam. She loves him.’ There is even talk that Rayner has been debating whether or not, in the event of her becoming Prime Minister, she should walk hand in hand into No 10 with Tarry. Some supporters insist she would because there is every indication that they plan to marry before such an eventuality.

Asked if Tarry would propose, a close source said: ‘Sam never comments on his private life.’

Whatever happens, Tarry’s Left-wing beliefs are no bar to him enjoying the high life with Rayner. A couple of years ago, she was spotted buying him suits in a Savile Row tailor’s shop. And for New Year in 2024, he and Rayner stayed five nights in the £2 million apartment – complete with jacuzzi and pool – of multi-millionaire Lord Alli, who donated £30,000 of clothes and designer spectacles to Starmer.

Would Tarry’s influence be felt in any Rayner government? Almost certainly. Tarry can count Climate Change Secretary Ed Miliband among his allies. What now worries Rayner’s many Labour opponents is that she will make net-zero fanatic Miliband her Chancellor, meaning even higher green taxes.

For a glimpse of how Britain’s workplace would change if Rayner and Tarry were given the keys to No 10, look at her Employment Rights Bill, in which she planned to give people the right to sue for unfair dismissal from their first day in a new job. That plan, which horrified employers, was watered down to six months after Rayner left government. Tarry was an advocate of the ditched proposal.

However, he was conspicuous by his absence when she made her most serious intervention in the nascent leadership race last month. Rayner was the star turn at an event for Mainstream, the Labour pressure group associated with Burnham, where she warned that the ‘very survival of Labour’ was at stake. Some supporters thought it was misjudged, too showy. ‘She’s already the favourite to be next leader,’ said one MP. ‘With what’s happening in the Middle East, her timing was terrible.’

Others argued the speech was flat and boring. Just like the robotic-sounding Chancellor, Rachel Reeves, who’s eschewed voice training, Rayner refuses to seek professional help for her public speaking. ‘She wants to sound authentic,’ said an admirer.

Before the speech, Rayner, who’s trying to cut back on her drinking, had downed glasses of white wine. She’s also tried and failed to give up vaping. ‘She’s hooked. Her kids want her to give up but she can’t,’ said the admirer.

Rayner has always been a party animal but another way she likes to unwind, I can reveal, is by listening to ‘true crime’ podcasts –the more horrific the better. ‘She loves retelling her staff the grisliest bits the next morning,’ said a friend. There is little doubt that she is relishing the grisly skewering of Starmer. And all the more so now that she feels the weight of the HMRC investigation beginning to lift.