The corruption trial of former Deputy President Jacob Zuma presents South Africa with its most serious political crisis since the end of apartheid 11 years ago.
BBC News, Durban
Jacob Zuma's sacking is seen by the left as a political assassination
In the dock is a man who, though it might be an exaggeration to call him South Africa's most popular politician, has in the last few months proved beyond reasonable doubt that his power to draw the crowds is unmatched.
And the crowds will again be on the streets on Tuesday as Mr Zuma appears in the Durban Regional Court for the charges to be read out.
The Congress of South African Trade Unions will be demonstrating; members of the Youth League of the governing African National Congress (ANC) have threatened to protest naked in support of their favoured leader.
Those who do wear clothes are likely to be wearing the T-shirts that have already appeared at previous demonstrations, bearing the words "100% Zuma".
Show of unity
The ANC leadership have been doing their best to convince their followers that the party remains united, and that support for Mr Zuma during his trial does not translate into a vote of no confidence in President Thabo Mbeki.
South Africa, after all, has a judiciary and a prosecution service that are not answerable either to the president or to any other branch of the executive.
Thabo Mbeki (left) and Jacob Zuma were formerly allies
Moreover, the charges against Mr Zuma followed the prosecution for corruption and fraud of his former financial adviser, Schabir Shaik; evidence aired at that trial suggested that Mr Shaik had been engaging in illegal activity to Mr Zuma's benefit, even if not actually with Mr Zuma's knowledge.
That evidence was enough for Mr Mbeki to dismiss his deputy - citing the need to send out a strong message against corruption - and for prosecutors to start investigating charges.
And few months ago, Mr Zuma himself was insisting that he be allowed his day in court to put an end to what he and his supporters saw as a trial by media, as the press and opposition demanded that he answer the questions raised during the Shaik trial.
But Mr Zuma's supporters remain convinced that the charges are politically motivated.
Unlike Zuma, Mbeki is not good at working a crowd
Their argument was buoyed by the news of a controversial armed raid by the Special Prosecutions Unit on Mr Zuma's home and offices in search of evidence; and by the fact that Phumzile Mlambo-Ngcuka, appointed by Mr Mbeki to succeed Mr Zuma as deputy president, is married to the man who initiated against Mr Zuma in the first place.
So, like it or not, this has become a political trial.
On one level, the choice is between individuals: Mr Zuma is simply better at working a crowd than Mr Mbeki, whose principal means of communicating with the public is a wordy and rather academic regular column published on the ANC website.
On another level, it is about policy. Mr Mbeki has led a government that has adopted conservative fiscal policies in pursuit of economic growth; in so doing, he has run the risk of alienating the ANC's core membership, and trade union and communist allies, who favour a more socialist approach.
His choice of Mr Zuma as a presidential running-mate in 1999 was motivated to a large extent by the need to keep these constituencies behind the ANC - and their loyalty to Mr Zuma has outlasted Mr Mbeki's alliance with Mr Zuma.
Analysts have hinted that whatever the result of the trial, the political fall-out will be hard to contain.
Zuma's supporters have set up a website ahead of his trial
If Mr Zuma is found innocent, a man who is already popular will become unstoppable.
His supporters will see the judgement as vindicating what they have been saying all along, namely that the trial was the product of a conspiracy - and others who have been keeping an open mind on the issue are likely to be swayed in Mr Zuma's favour.
In such a case, a Zuma presidency seems inevitable.
Yet if that day comes, President Zuma - and, by association, the government he leads - will forever be haunted by the evidence that was aired at the Shaik trial.
South Africans who value the rule of law, as well as foreign investors, will be dismayed at a judgement that leaves unanswered questions about corruption, and which will be read as a case of judges being swayed by pressure from the streets.
Rule of law
If, on the other hand, Mr Zuma is found guilty, a large and vocal sector of the body politic will be convinced that their man has been brought down by a conspiracy involving the government operating with the complicity of the judiciary.
Shaik's trial prompted the new inquiry into Mr Zuma's conduct
Mr Mbeki will be isolated within his own party until he steps down in 2009, and the choice of candidate to succeed him to the leadership of the ANC and the country will be determined by who can win the confidence of the Zuma camp.
More serious will be the damage to South Africa's efforts to establish a democracy based on the rule of law.
It is only in the past 11 years that South Africa has had the opportunity to start building institutions of state such as a judiciary that operates independently of government.
The demonstrations of the last few weeks reveal a popular belief that the judiciary has not moved on since the days of apartheid.
For Mr Zuma's supporters, a guilty verdict will be an indictment not of their favourite politician, but of the courts themselves.