Speculation is swirling about who could be Pope Francis's successor after his death.
But because of the way new popes are elected, it can be a complex question to answer.
Let's unpack how a pope is chosen and look at some of the people Vatican researchers reckon could be contenders for the position.
They have to be elected by a vote.
Only cardinals — who are the second-highest-ranking members of the church under the pope — vote in this election.
And that's only if they're under the age of 80.
There are currently 136 cardinals in that category, according to the Vatican press office's cardinal dashboard.
A candidate has to win two-thirds of the vote to be elected as the new pope.
This vote happens in a secret meeting called a conclave, which can last days, weeks, or months, with four votes a day until a new pope is chosen.
They cast their votes in the Sistine Chapel and live in the dormitories in an on-site boarding house called the Casa Santa Marta.
While all this is going on, they're not allowed to have any contact with the outside world to ensure they don't have outside influences — which keeps the whole process very, very secret.
And this veil of secrecy means it's difficult to pick a single frontrunner.
Technically, any baptised Catholic male can be elected for the top job.
But the pope has been picked from the pool of cardinals for hundreds of years — so it's extremely likely the next pope will be a cardinal.
A cardinal over the age of 80 could become the pope, Catholic historian and commentator Paul Collins says, but he says that would be unlikely.
Not under the current rules.
"The reality is that the patriarchy is still entrenched and women need not apply," Dr Collins says.
Because the whole process is so secretive, it's really just speculation and educated guesswork.
So we're looking to Catholic media for commentary.
Dr Collins, who was a Catholic priest for 33 years until he resigned in 2001 due to a "doctrinal dispute", thinks there are four major contenders — cardinals we've listed below in alphabetical order.
However, he is quick to point out that it is just his opinion and it's wise to "discount nothing" when it comes to picking a new pope.
Dr Collins says Cardinal Matteo Zuppi could be the next pope, listing fellow progressives Pietro Parolin and Luis Tagle as close alternatives.
He thinks Péter Erdő would be the pick for conservatives.
Age: 72
Birthday: June 25, 1952
Country: Hungary
Cardinal Péter Erdő was ordained as a priest in 1975 and has a doctorate in theology.
He has authored more than 250 scholarly articles and written 25 books.
"He is more Catholic than you can possibly be," Dr Collins says.
He reckons Cardinal Erdő is a top pick for conservatives within the church.
"He will be the candidate of those who want to move away from Pope Francis's agenda completely," Dr Collins says.
The authors of his profile on the College of Cardinals Report website say he was "a favourite of the late Cardinal George Pell", who saw him as "someone who could above all restore the rule of law in the Vatican after [Pope Francis]".
"Pell was his [supporter]," Dr Collins says.
"That tells you everything."
Age: 67
Birthday: June 21, 1957
Country: Philippines
Cardinal Louis Antonio Gokim Tagle was ordained as a priest in 1982 and became a cardinal four decades later in 2012.
He can speak Tagalog, English, and Italian.
"Tagle is humble, deeply spiritual, charismatic, with an excellent sense of humour," Dr Collins says.
Dr Collins says Tagle has been a more likely candidate in the past, and his chances have been hurt in recent years because of his handling of Caritas — the Catholic church's major charity.
He says there had been some "real administrative problems" within the organisation because of a few "duds" running things.
And Dr Collins says Tagle had appointed some of these "duds".
"He fell out of favour, which is sad because Tagle is a smart guy. He's not a dill."
"He confuses Westerners because he's very strong on social justice but [not] when it comes to some of the gender issues."
Dr Collins says he tends to be in line with "pretty conservative" bishops in Millina.
It's unclear if Tagle supports blessing same-sex couples, but in the past he has criticised the Catholic church's "harsh words" against gay people, single mothers and divorcees.
Age: 70
Birthday: January 17, 1955
Country: Italy
Cardinal Pietro Parolin was ordained in 1980 and speaks Italian, French, Spanish and English.
He's been the Vatican's secretary of state since 2013.
Dr Collins explains this as being "the pope's prime minister and foreign minister combined".
And while this makes him the number-one contender in some commentators' eyes, Dr Collins says he has one thing working against him.
"He has virtually no pastoral experience in a parish or the administration of a diocese," he says.
"That won't do well with the cardinals within the developing world, who are very strong on the need with someone for pastoral experience … dealing with people at the bottom level."
He is against ordaining women as priests, with the Catholic National Register quoting his 2023 letter saying there is "no possibility" of the church taking a different view on banning female priests.
Age: 69
Birthday: October 11, 1955
Country: Italy
Cardinal Matteo Zuppi was ordained as a priest in 1981.
"He's a very smart guy," Dr Collins says.
Cardinal Zuppi was a priest in a local parish in Rome and he is the archbishop of Bologna.
On top of this, he has substantial diplomatic experience, which Dr Collins says adds to his favour.
"He's been the pope's guy in negotiations with Ukraine … negotiating on behalf of the pope with [former US president] Joe Biden."
Critically, he helped broker peace in Mozambique in 1992 after more than a decade of civil war by working as a mediator in negotiations.
"The man on the ground in Zuppi … he has respect in Africa," Dr Collins says.
"He's the type of bloke they'd go for."
Cardinal Zuppi is in favour of blessing same-sex couples, having publicly backed Pope Francis's pro-blessing stance in 2024.
And he's indicated he's open to the idea of allowing married men to become priests, telling journalism students at an event in 2023 that the rule restricting priests to a life of celibacy is a rule that "can be changed".
At that same event, he appeared to be against the idea of ordaining women as priests.
But Dr Collins is just one of many Catholic commentators.
Another provider of such speculation is The College of Cardinals Report, a website run by an "independent team of Catholic journalists and researchers" led by Edward Pentin and Diane Montagna.
It lists the four cardinals Dr Collins mentioned above, along with 18 others its writers reckon could be in with a chance of being the next pope:
Age: 75
Birthday: September 24, 1949
Country: Sweden (but he was born in Switzerland)
Cardinal Anders Arborelius, who adopted Catholicism when he was 20 years old, was ordained as a priest a decade later in 1979.
He has a masters in modern languages, studied the standard philosophy and theology most priests study, and speaks Swedish, English, Spanish, French, German and Dutch.
Cardinal Arborelius is described as "genuinely meek and humble" in the College of Cardinals Report website's profile on him....
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