Chinese micro-bloggers and overseas websites have come up with all kinds of speculation as to why the current vice president and the president-in-waiting Xi Jinping has gone unseen for over a week.
During that span, Xi cancelled meetings with visiting foreign dignitaries including US secretary of state Hillary Clinton and Singapore Prime Minister Lee Hsien Loong.
On Monday, it was the Danish Prime Minister's turn.
On Sunday, he also missed an emergency meeting of the Central Military Commission, of which he is a vice chairman, called to discuss earthquake recovery work.
Xi's whereabouts during this sudden absence from the spotlight may never be known. One thing, however, is certain: China may now be a linchpin of the global economy and a force in international diplomacy, but the lives of its leaders remain a mystery to its 1.3 billion people.
So when the presumptive head of that opaque leadership disappears from public view, rumour mills naturally go into a frenzy.
"There is a longstanding practice of not reporting on illnesses or troubles within the elites," said Scott Kennedy, director of Indiana University's Research Centre for Chinese Politics and Business in Beijing.
Most online speculation about the portly 59-year-old Xi has centered on a back problem, possibly incurred when he took a dip last week in the swimming pool. Another rumour has the back being hurt in a soccer game. It wasn't clear what the sources of the information were.
The US-based website Boxun.com cited an unidentified source as saying Xi was injured in a staged traffic accident that was part of a revenge plot by the supporters of Bo Xilai - once a political heavyweight - in the security forces.
As if to demonstrate the range and randomness of the speculation, Boxun later replaced the report with another saying Xi was merely preoccupied with preparations to take over as head of the ruling party.