The race is now on to replace Liz Truss as leader of the Conservative Party and become the new prime minister of the United Kingdom, and three familiar faces are leading the charge.
Ms Truss was in the top job for just 44 days before announcing her resignation, and will go down as the shortest-serving British prime minister in history.
And the man she replaced, Boris Johnson, is among the favourites to assume the role.
In an abridged version of the leadership contest (the last one took nearly three months) candidates will need at least 100 nominations before 2pm on Monday from the 357 Conservative MPs that sit in the House of Commons to be in the running.
This means only three candidates can be in the running, and if only one has the required 100 nominations by Monday's deadline they would automatically become prime minister.
If three candidates reach the threshold, a ballot of MPs would be held on Monday afternoon to narrow it down to two.
Those two final candidates would be put to an online vote of 172,000 Conservative Party members, with the winner announced on Friday.
So far only one MP – House leader Penny Mordaunt – has announced herself as a candidate.
But other Tory MPs have been voicing who they would vote for, and only two other names have been mentioned: Rishi Sunak, and former prime minister Boris Johnson.
The magician's assistant who became a top Tory
The Leader of the House of Commons, Penny Mordaunt stood in for Liz Truss on Tuesday when the Labour opposition asked an urgent question in Parliament on why the government had reversed the vast majority of her mini-budget.
The moment gave her a taste of life in the top job, but was also seen as another embarrassing moment for Ms Truss, who was accused of "cowering under her desk and asking for it all to go away" by a Labour MP.
As Lord President of the Council Ms Mordaunt also had a prominent role in the transition from Queen Elizabeth II to King Charles III, presiding over his Accession Ceremony in September.
Ms Mordaunt, 49, was a passionate supporter of leaving the European Union and made national headlines by taking part in a now-defunct reality TV diving show called Splash! in 2014.
A reservist with the Royal Navy, Ms Mordaunt was the first woman to be defence secretary, but she only lasted 85 days in the job — being sacked by Mr Johnson when he became prime minister after she endorsed Jeremy Hunt during the 2019 leadership contest.
She also worked as a magician's assistant to help fund her university studies, working alongside the president of the British Ring of The International Brotherhood of Magicians.
In the last leadership contest she made it to the final three candidates during the run-off vote of MPs, getting 105 votes to Liz Truss's 113 and Rishi Sunak's 137.
So far she has had the lowest number of MPs publicly backing her.
The richest man in the House of Commons
Rishi Sunak capped off a meteoric rise from the backbenches in February 2020 when Boris Johnson appointed him the new Chancellor of the Exchequer — or treasurer — at the age of 39.
He was praised for a COVID-19 economic rescue package, including a costly jobs retention program that averted mass unemployment.
But Mr Sunak later faced criticism for not giving enough cost-of-living support to households.
But the relationship of Mr Sunak and Mr Johnson would later break down – Mr Sunak's resignation from the role on July 5 was the catalyst for half of the Johnson cabinet quitting.
When resigning he said the British public "rightly expect government to be conducted properly, competently and seriously".
Mr Johnson was forced to stand down just two days later.
Prior to becoming an MP in 2015, Mr Sunak was a banker and hedge fund manager, and some British media outlets have valued his net worth at 200 million pounds (A$353 million), but this is mainly down to his wife Akshata Murthy, who is the daughter of Indian billionaire NR Narayana Murthy, founder of IT company Infosys.
And revelations about his wealthy wife's non-domiciled tax status and a fine he received, along with Mr Johnson, for breaking COVID lockdown rules damaged his standing among the public.
Getting the most votes from Conservative MPs in the last leadership ballot, Mr Sunak battled it out with Ms Truss over several months to put his case forward that he was the best person to lead the party and the country.
Ultimately it failed, with Ms Truss getting 57 per cent of the vote and becoming prime minister.
He is currently the frontrunner, with more than 50 MPs declaring they will be backing him before Monday's vote.
The return of Boris?
In his final speech as prime minister on September 6, Boris Johnson referenced the Roman statesman Lucius Quinctius Cincinnatus, who helped protect Rome from invasion before returning to life on his farm.
"Like Cincinnatus, I am returning to my plough and I will be offering this government nothing but the most fervent support," he said outside of Downing Street as Liz Truss was being appointed prime minister by the late Queen at Balmoral.
What he didn't mention was the fact Cincinnatus was later recalled to Rome to lead as dictator, a point of which the history-buff former PM would have been fully aware.
And now, just over a month later, Mr Johnson is reportedly flying home from his Caribbean holiday with his young family to return to London and assume the mantle that he felt destined to hold since his youth.
Mr Johnson has his backers – including three current cabinet members – but some Conservative MPs said they would even leave the party and sit as independents if he was returned as leader after a series of scandals that plagued his time as prime minister and saw him resign in disgrace.
Incredibly popular with grassroots Tories, if Mr Johnson can make it to the final two candidates he would likely win the vote of the Conservative Party membership.
But his biggest battle will be convincing the MPs that turned on him that he deserves a second chance.
