By Joseph Winter
Pius Ncube is widely believed in Zimbabwe to be the latest victim of dirty tricks by the feared Central Intelligence Organisation (CIO).
Archbishop Ncube - many believe he was a victim of CIO agents
Bishop Ncube, who has just resigned as the Archbishop of Bulawayo, has been a vocal critic of the government.
In July this year, he called for foreign intervention to remove President Robert Mugabe.
A week later, he called the president a "megalomaniac, a bully and a murderer".
Barely two weeks after that, state media gleefully published photos - allegedly of Bishop Ncube in bed with a married woman.
The bishop denies the allegations, but whatever the truth the scandal has led to his resignation, with her husband suing him for damages.
"The CIO manufactured all that," says Tendai Biti, secretary general of one faction of the opposition Movement for Democratic Change (MDC).
"He fought the regime and the regime fought back."
ALLEGED DIRTY TRICKS
Pius Ncube - adultery
Morgan Tsvangirai - treason plot
MDC - infiltration split
Ndabaningi Sithole - attempted assassination
Bishop Ncube himself talks of the "crude machinations of a wicked regime" but vows: "I will not be silenced".
He has, however, lost his job and it remains to be seen whether his voice will carry the same influence without the backing of such an influential post.
Lovemore Madhuku from the National Constitutional Assembly, which campaigns for political reform in Zimbabwe, says that as soon as you stand up and criticise the government, you are taking a huge risk.
Opposition activists have been beaten up, tortured and even killed but CIO agents also employ subtler methods, such as those many believe were used against Bishop Ncube.
"They visit your husband, or your wife, or your workplace and try to interfere in your day-to-day life," Mr Madhuku told the BBC News website.
Madhuku: the CIO find ways to interfere in your day-to-day life
"They are very clever," he says. "They cannot force you to have an affair but they study you, so they can take advantage of your weaknesses."
He says that other favoured methods are to entrap businesspeople into doing something illegal, like dealing in foreign currency.
They then keep this information and use it against you when they judge the time is right, blackmailing you into giving up politics.
Mr Madhuku says CIO agents have repeatedly gone to the University of Zimbabwe, where he works in the law faculty, to try to get him sacked.
He says they have successfully managed to stop him taking a high-profile role in his church.
The CIO reports directly to the office of the president and agents are selected on the basis of their loyalty to Mr Mugabe and his Zanu-PF party.
It has a massive budget despite Zimbabwe's economic woes, access to the latest technology and a massive network of informers.
"You don't know who you're talking to, who you can trust," Mr Biti says.
Mr Tsvangirai was acquitted after a long treason trial in Harare
He says they have infiltrated every structure of every organisation in the country. And opposition parties are first in their firing line.
Two years ago, the MDC, which has presented Mr Mugabe with its strongest challenge since he led Zimbabwe to independence in 1980, split into two factions, making it far less effective.
Many see this as another CIO coup.
Mr Madhuku alleges their agents infiltrated the highest levels of the party and successfully played on the egos of top MDC officials to engineer a split.
Although the government denied involvement at the time, this was not the first time that MDC leader Morgan Tsvangirai had been targeted.
Just weeks before the 2002 presidential election, he was charged with treason, based on the evidence of Ari Ben-Menashe, a Canada-based political consultant.
Grainy footage of the CCTV tape of Mr Tsvangirai (R) was sloppy
He testified that in a secretly-filmed meeting in December 2001, Mr Tsvangirai had asked him to arrange the assassination of President Mugabe.
As evidence, he produced a grainy tape-recording.
However, on that occasion, the CIO's standards had slipped and it was obvious that the tape had been heavily edited in an amateurish attempt to put incriminating words into Mr Tsvangirai's mouth.
The clock in the corner of the CCTV footage kept on flicking backwards and forwards.
With its tentacles reaching into every facet of Zimbabwean life, the CIO no doubt tried to ensure that a compliant judge heard the case.
But for whatever reason, on this occasion, their plans failed and Mr Tsvangirai was acquitted.
Nevertheless, the possibility of a death sentence must have been a huge distraction for the opposition leader for more than two years, making him less of a threat to Mr Mugabe.
He was not the first opposition leader to be tried for treason on spurious grounds in Zimbabwe.
Reverend Ndabaningi Sithole, Mr Mugabe's rival for more than 20 years, always claimed that he had been set up when he was charged with trying to assassinate Mr Mugabe in 1997.
On this occasion, he was found guilty and sentenced to two-and-a-half years in prison, although he died, aged 80, before serving any time.
Before the treason charges, another CIO ploy to discourage one of only two opposition MPs at the time, had been to show Rev Sithole a document allegedly showing that his wife was having an affair with a government minister.
Mr Madhuku says such petty interference, as much as the threat of physical violence, is why many ordinary Zimbabweans decide not to get involved in politics, despite the country's economic collapse.
Mr Biti says Mr Mugabe owes his position to dirty tricks and the 'securicrats' who invent them.
"They are the real brains of this regime."