Rishi Sunak was 42 when he became prime minister last year, making him the youngest holder of the office in modern times.
He is also the first British-Indian to be prime minister. The son of first generation immigrants, who worked hard to send him to one of the country's top fee-paying schools, Winchester College, where he was head boy.
He spent time in California and worked at investment bank Goldman Sachs - and two multibillion dollar hedge funds - before entering politics.
A self-confessed "huge Star Wars fan" with a sizeable collection of lightsabers, he is sometimes portrayed as a "geek". He generally swears off alcohol in favour of Mexican Coca-Cola, which, he says, is made with "cane sugar rather than high fructose corn syrup".
Colleagues describe him as a details man, who is always the best-briefed person in any meeting.
He became prime minister in extraordinary circumstances after his predecessor Liz Truss - the woman he lost to in a leadership contest after the collapse of Boris Johnson's turbulent premiership - quit after just 45 days in the job.
His first job was to steady the ship. He is now trying to reinvent himself as an agent of change, someone who can make difficult long-term decisions.
With the Conservatives trailing Labour by a long way in the opinion polls, and an election that must be held before January 2025, he has a mountain to climb if he is to remain in office.
Image source, HM Treasury / Flickr
Rishi Sunak: The basics
Age: 43
Place of birth: Southampton, Hampshire
Home: London and Yorkshire
Education: Winchester College, Oxford University, Stanford University
Family: Married to businesswoman Akshata Murty with two daughters
Parliamentary constituency: Richmond (Yorkshire)
Watch: Rishi Sunak says that when it comes to helping the most vulnerable "that's what I did".
Where is Rishi Sunak from?
Mr Sunak's parents came to the UK from east Africa and are both of Indian origin.
He was born in Southampton in 1980, where his father was a GP, and his mother ran her own pharmacy.
"In terms of cultural upbringing, I'd be at the temple at the weekend - I'm a Hindu - but I'd also be at [Southampton Football Club] the Saints game as well on a Saturday - you do everything, you do both."
In the interview he said he had been fortunate not to have endured a lot of racism growing up, but that there was one incident that had stayed with him.
"I was just out with my younger brother and younger sister, and I think, probably pretty young, I was probably a mid-teenager, and we were out at a fast food restaurant and I was just looking after them. There were people sitting nearby, it was the first time I'd experienced it, just saying some very unpleasant things. The 'P' word.
"And it stung. I still remember it. It seared in my memory. You can be insulted in many different ways."
However, he said he "can't conceive of that happening today" in the UK.
Image source, PA MediaHe attended Winchester College and worked as a waiter at a Southampton curry house during his summer holidays.
After finishing school he went on to Oxford to study philosophy, politics and economics, before studying for an MBA at Stanford University in California. There he met his wife, and the couple have two daughters.
His rise to the top of British politics has been rapid - he only became an MP in 2015, in the rock solid Conservative seat of Richmond, in North Yorkshire.
His political opponents have made much of his personal wealth, claiming he is out touch with the lives of most voters.
Who is Rishi Sunak's wife?
Together, he and his wife Akshata Murty - daughter of Indian billionaire Narayana Murthy, who co-founder of IT services giant Infosys - have an estimated worth of more than 拢700m.
Last year, Ms Murty announced she would start paying UK tax on her income to relieve political pressure on her husband.
Image source, Getty ImagesHe was arguing for Britain's departure from the EU from his earliest days in politics and supported the Leave campaign in the 2016 Brexit referendum.
But he first came to wider public attention during the coronavirus pandemic, when as the recently-appointed chancellor he spent eye-watering sums on the furlough scheme and other support measures, as well as launching the controversial Eat Out to Help Out scheme.
His personal popularity soared but he also got caught up in the Partygate controversies that rocked Downing Street, being fined, in June 2020, for attending one of the now infamous gatherings.
And he found himself increasingly at odds with his boss Boris Johnson over the economy - pushing for lower taxes and spending cuts.
In July last year, he resigned from the cabinet, a move that was instrumental in ousting Mr Johnson, which some of the former PM's allies have not forgotten.
He was not elected leader by Conservative Party members. He was effectively crowned by Tory grandees, who were desperate for someone to steady the ship after the chaos of Liz Truss and Boris Johnson.
He inherited a financial crisis and a party in disarray but also a near 70-seat majority - which has since been eroded by two embarrassing by-election losses.
At the start of the year Mr Sunak set out five promises to voters, he wanted to be judged by:
- Halving inflation
- Growing the economy
- Reducing debt
- Cutting NHS waiting times
- Passing new laws to stop small boat crossings
In September, he delayed a ban on new petrol and diesel cars in a major change to the government's approach to achieving net zero by 2050. seeking to portray himself as the friend of the motorist and voters who are unhappy about the personal sacrifices required to reach the net zero target.
He is also scaling back the HS2 high speed rail link.
He is hoping this will make him look bold and decisive, but Labour have attacked him as someone who dithers over decisions, dubbing him "inaction man".
With an election possible as early as next spring, he will be fervently hoping that his first conference speech as Tory leader and prime minister will not be his last.
