For almost 15 minutes last Sunday evening, many Singaporeans did not know what had happened to their Prime Minister.
The audience at ITE College Central saw Mr Lee Hsien Loong suddenly go quiet, struggling to hold on to the podium before he was led offstage, supported by Defence Minister Ng Eng Hen.
Television viewers watching the National Day Rally live had an even more anxious time because they thought he might have collapsed on stage, the cameras having panned away from him by then. They did not know he was able to walk off, and even managed a wave.
"PM collapsed?" became the most-asked question on social media for several minutes.
The answer could not have come sooner when it was announced that the medical team treating him had assessed his condition as "not serious". But there was more.
When PM Lee returned to the stage, he made the comeback speech of the year.
It was a remarkable recovery because he did not look or sound like someone who had, 80 minutes ago, been on the verge of collapsing. In fact, he looked more relaxed than he had been in the more than two hours he had been speaking for earlier. And the point he made immediately after resuming was, for me, the most significant in the rally.
This was what he said: "...What happened makes it even more important that I talk about it now... Nothing that has happened has changed my timetable or my resolve to press on with the succession.
"In the next GE (general election), we will reinforce the team again, and soon after the next GE, my successor must be ready to take over."
He couldn't have raised the issue more dramatically.
Leadership renewal has been a trademark of the People's Action Party's brand of politics since the 1970s, one it takes as seriously as life and death.
This is as it should be.
The carefully honed system of scouring the island for political candidates and an equally systematic selection process meant that although many worried over the PM's health, there was no alarm that Singapore would be leaderless should something worse have happened to him.
The two deputy prime ministers stand ready to take over, backed by an experienced team. But the method has its limitations.
One obvious weakness is the bias towards those in the public service, including the military. Of the handful of younger ministers said to be in the running for the top job, all are former civil servants or military officers.
The dangers of groupthink are well known, but there is also the other problem of deterring those from a different background from joining the select group.
A system that is perceived to favour those from the public service will naturally deter outsiders.
It is a problem in a small country like Singapore in other areas beyond politics whenever there is ingrained thinking that there is only one way to achieve success.
Perhaps it's the reason there are no Singaporean Nobel Prize winners. Before Joseph Schooling's historic gold medal, I might have added Olympic champions to the list.
But, in fact, his win reinforces the point that to be a world-beater, you must be prepared to go against the convention. Schooling's parents did what most here would never do - back their son all the way in his quest for sporting glory, even selling an overseas property to fund his training in the United States.
They were mavericks in the system and their gamble paid off.
The other issue about leadership succession has to do with how the PM is finally chosen.
If it follows the previous script, it is likely that some time between now and the next GE, the appointed successor will break away from the field and be promoted to a senior position to signal his anointment.
Who makes the decision, apart from the PM, though isn't clear.
Singapore's ruling party does not have a formal system of choosing its leader (who becomes PM since the party has the most seats in Parliament).
In Britain, the Conservative Party leader is chosen by MPs who vote for their choice in a leadership contest.
That was how the current PM, Mrs Theresa May, was chosen in several rounds of voting, after Mr David Cameron resigned abruptly following the Brexit referendum.
The Labour Party's selection is done by a much wider pool of voters who are registered members of the party and not just among elected MPs.
In Japan's governing Liberal Democratic Party, Diet members and the party's prefectural representatives vote for their leader. Candidates for the party leadership must be endorsed by at least 20 members.
In the US, the complicated process is a long-drawn-out affair of primary elections, leading to a party convention where the candidate is formally chosen.
Obviously there isn't a right or wrong way, and every party has to decide how best to do it.
In fact, the PAP does have an election, not to choose the PM, but to elect its Central Executive Committee (CEC) every two years.
Party cadres vote in the top 12 from a shortlist of candidates into the CEC, and up to six can be further co-opted.
Should the party do so similarly to choose the next PM?
It isn't clear such a system will work because it is unlikely there will be many contending candidates. It is just not the done thing here for anyone to put himself up for the party leadership.
But it shouldn't also be such an opaque decision that no one knows what is happening until the succession announcement is made.
Being more open and transparent would help Singaporeans understand better why a particular person was chosen and how the assessment was made.
It would be good if the ruling party discussed openly the merits of various ways in which this could be done.
It should make for good politics.