The overnight rally planned by electoral reforms activist group Bersih to begin this afternoon will undoubtedly see tens of thousands descending on the streets of the capital, in what has become a protest against Prime Minister Najib Razak.
The size of the crowd will determine the amount of added pressure on the embattled Malaysian leader, who is already fighting on several political and economic fronts after becoming embroiled in a controversy over US$700 million (S$960 million) deposited into his personal accounts, which the government has called "political donations".
But no matter how many gather, it is unlikely that Datuk Seri Najib will step down as a result, having already shown he is willing to take drastic and unpopular measures to remove threats to his leadership.
The question is how far his Cabinet, which underwent a reshuffle last month that saw critics including his deputy premier replaced, will be able to stomach such an open show of disapproval.
The city administration and police have been inconsistent in their handling of the impending rally - on the one hand claiming that it is illegal but, on the other, saying that they hope to facilitate a peaceful event that will not end up with volleys of tear gas and water cannon as seen in three previous Bersih rallies.
But Internet regulators have already blocked Bersih's website, and the Education Ministry is barring teachers from attending the gathering that Bersih plans to conclude on the stroke of midnight of Aug 31, Independence Day.
An initial survey has shown that fewer than a quarter of Malays support the rally. Should this play out on the ground, Mr Najib and his allies may see a clampdown as strengthening their position within the ruling Umno, where there are rumbles against his removal of dissenters in his Cabinet.