When the opposition-controlled South Korean parliament voted to impeach President Yoon Suk Yeol over a short-lived attempt to impose martial law, it ended days of political paralysis in the country.
But it also brought a level of uncertainty — alongside an intense debate over Mr Yoon's fate and the future of the nation.
On Monday, the Constitutional Court met for the first meeting over the impeachment, and investigators said they planned to question Mr Yoon this week.
But what is the likelihood the court will uphold the impeachment? And where to now for South Korea and its president?
First, who's running the country?
Mr Yoon was removed by South Korea's parliament on Saturday over his short-lived attempt to suspend civilian rule, which plunged the country into its worst political turmoil in years.
Shortly after Mr Yoon was impeached, technocratic Prime Minister and Acting President Han Duck-soo stepped in as interim leader, moving swiftly to reassure the country's allies and calm financial markets.
Mr Han will govern the country for a maximum of eight months, depending on how long the court deliberates on the impeachment motion and what it decides to do.
In his first address to the nation as acting president, Mr Han vowed to "ensure stable governance".
"I will devote all my strength and efforts to ensure stable governance," the 75-year-old career bureaucrat said.
Impeachment trial begins
On Monday, all six current justices of the court attended South Korea's Constitutional Court first meeting about the impeachment.
Mr Yoon's presidential powers have been suspended but he remains in office, retaining his immunity from most charges except for insurrection or treason.
Justice Kim Hyung-du said the Constitutional Court would discuss procedures and how to conduct arguments.
The Constitutional Court must decide within 180 days whether to remove Mr Yoon from office or reject the impeachment and restore his powers.
Under South Korea's constitution, six justices must agree in order to oust an impeached president.
The nine-member Constitutional Court now has three vacancies, so the current justices would have to vote unanimously to remove Mr Yoon.
If the court removes Mr Yoon or he resigns, a national election to choose his successor must be held within 60 days.
Opposition Democratic Party MP Jung Chung-rae, the head of parliament's Legislation and Judiciary Committee, will lead the case for removing Mr Yoon.
What's the likelihood the court will uphold the impeachment?
In South Korea's only previous presidential removal by impeachment, the court took three months to oust Park Geun-hye in 2017.
The court began oral arguments about three weeks after parliament voted to impeach the then-president over abusing the powers of her office.
This time, the terms of two court justices expire in April, and legal experts predict the court may seek to rule before then to minimise uncertainty.
In the past, academics say, Constitutional Court justices have not voted predictably by political leaning but have instead decided each case based on their interpretation of the constitution.
Mr Yoon and a number of senior officials face potential charges of insurrection for the short-lived martial law declaration.
A joint team of investigators from the police, the defence ministry and an anti-corruption agency are planning to call Mr Yoon in for questioning on Wednesday morning, a police official told Reuters.
Legal experts say it is very likely the judges will remove him, given the clear constitutional violations involved in his martial law declaration.
Chang Young-Soo, a law professor at Korea University, told the Associated Press he believed there was a "50-50 chance" of Mr Yoon being removed from office and it would depend on the evidence.
"If there is no further evidence beyond what President Yoon has been saying, in other words, if there is no evidence that proves what the chief of army special warfare command had said, there won't be any way to recognise the charge of rebellion," he said.
"In that case, the charge of rebellion won't be recognised in court, which can also lead to the conclusion that the impeachment cannot be recognised."
Kim Hyun-jung, a researcher at the Korea University Institute of Law, told AFP it was clear Mr Yoon "aimed to paralyse the state's functions".
"Even the most conservative scholars acknowledge this has caused a crisis in constitutional order," Mr Kim said.
Who might be the next president?
South Korea's opposition leader, Liberal Democratic Party leader Lee Jae-myung, is seen as the frontrunner for the presidency, analysts say.
In the 2022 election, Mr Lee lost to Mr Yoon by the narrowest vote margin in South Korea's electoral history, with a gap of about 0.7 per cent.
Mr Lee urged the Constitutional Court to rule swiftly on the bid to remove Mr Yoon from office and proposed a special council for policy cooperation between the government and parliament.
He told a televised news conference that a swift court ruling would be the only way to "minimise national confusion and the suffering of people".
But his bid for the presidency has been overshadowed by a series of scandals, including a court ruling in November finding him guilty of election law violations, resulting in a suspended sentence.
If the verdict is upheld, he will not be eligible to run for office.
South Korean ruling party chief resigns
Han Dong-hoon, the leader of Mr Yoon's conservative People Power Party, was seen as a potential contender for the presidency but he announced his resignation on Monday in the wake of Mr Yoon's impeachment.
"I step down as the leader of the People Power Party," Han Dong-hoon told a televised press conference on Monday.
"I sincerely apologise to all the people who have suffered due to the emergency martial law incident".
Mr Han had not been linked to the martial law bid and expressed support for impeachment.
He condemned on Monday "extremists such as election fraud conspiracy theorists" and warned "there will be no future for conservatism" if the party entertained those views.
ABC/wires
