Forty-one-year-old Neil Heywood was found dead in a hotel room in Chongqing, China's biggest metropolis, last November. His death was initially attributed to alcohol poisoning.
On April 10, authorities made the surprise announcement that Gu Kailai - the wife of the region's former Communist Party chief, Bo Xilai, was being investigated on suspicion of murder, along with a family aide, Zhang Xiaojun.
The same day Bo was suspended from the Communist party's Central Committee. "Comrade Bo Xilai is suspected of being involved in serious disciplinary violations," said the Chinese news agency Xinhua.
The implication of a high-flying politician's wife in a murder would be shocking enough. But additional threads are emerging in what has become one of China's most spectacular political scandals.
On Monday, Reuters reported that Bo's wife Gu Kailai had hatched a plan to kill Heywood after he threatened to expose her attempts to move a large sum of money abroad. The story cited two unnamed sources "with close ties to Chinese police" as saying that Gu became angry after Heywood demanded a larger cut of the money than she had expected.
Reuters cited the sources as saying Heywood was poisoned by a drink. They did not know exactly where he had died in Chongqing.
The news agency said the Chinese authorities had not responded to its questions about the case.
Heywood's body was cremated days after his death, without an autopsy. British authorities have since pushed for a further investigation into his death.
But conspiracy theories are thriving as the investigation unfolds, with claims on one Chinese-language website that Heywood had even been poisoned by State Security agents in an effort to thwart Bo's political ambitions.
In the days after Bo's sacking as the Chongqing party chief in mid-March, a storm of rumors spread on social networks within China, speculating about the reasons behind the charismatic leader's demise.
Chinese censors worked quickly to silence the rumors by shutting down comment sections on the country's leading microblogging sites for two days in early April.
The latest theories about Heywood's death have been shared on sites within China, suggesting that the authorities are content to let these particular rumors fly.
"In China, if they want to discredit you they will let the rumors fly whether they're true or not. It may be a way of hosing down his support base," said Michael Keane, an associate professor at the Queensland University of Technology.
The scandal started unfolding publicly in early February when Wang Lijun, a decorated policeman who served as Chongqing's police chief from 2009 to 2011, was reported to be "on leave" for health reasons. It was soon revealed that he had fled to the U.S. consulate in Chengdu, six hours' drive away from Chongqing.
The lack of information about Wang's intentions and his whereabouts has also fanned online rumors.
Outside China, efforts to reveal more about the unfolding scandal have spread to the U.S. According to the Wall Street Journal Bo's son, 24-year-old Bo Guagua, has left his apartment in Cambridge, Massachusetts close to Harvard University, where he was studying.
The Wall Street Journal quoted the concierge as saying that staff at the building had been told not to answer questions, but declined to say who gave the instruction.
That report, and others, are being read in China, prompting complaints on microblogging sites about the lack of information coming from within the country.
So far China's official media have confined their coverage of the Bo scandal to terse news bulletins. In recent days, however, they have been running commentaries and articles which claim there has been widespread support within China for the authorities' handling of this issue.
A commentary published Saturday begins: "The recent decision of the Communist Party of China (CPC) Central Committee to investigate Bo Xilai's serious discipline violations, and the police reinvestigation of Neil Heywood's death, have garnered wide support from all walks of life in the country."
That article, along with others, claims that the investigations are an indication of Beijing's commitment to the rule of law.
In another article to be published Monday in the Communist Party magazine "Qiushi" or "Seeking Truth," Chinese Premier Wen Jiabao promised "more resolute measures" to combat corruption, Xinhua reported.
"Governments at all levels which are under-performing, allow important cases of corruption to occur, or fail to handle corruption cases in a timely manner will be held accountable,' Xinhua said, referring to the article.