BANGKOK The rare outsiders who meet him say he can be friendly and engaging, but behind the smile of "the old man" at the top of Myanmar's junta lies the heart of a cold, calculating military tactician.
Although dissidents, exiles and many of the former Burma's 56 million people like to paint the bespectacled 74-year-old Than Shwe as a paranoid despot driven by a mixture of greed, fear and superstition, the image is more cartoon than reality.
Nobody stays at the helm of one of the world's most ruthless regimes for 15 years without being smart, cunning and uncompromising.
In Than Shwe's case, the latter is especially true in his relationship -- or rather the lack of one -- with the opposition pro-democracy camp, led by detained Nobel peace laureate Aung San Suu Kyi, whom he is widely believed to loathe.
"Than Shwe is a such an old fox and a psychological warfare guy, I don't believe he will personally cave in. I don't see him as a compromiser. There is a lot of history between them," said Bradley Babson, a retired World Bank Myanmar expert.
Although no details have emerged of his meeting on Tuesday with United Nations special envoy Ibrahim Gambari, sent in to end a bloody crackdown on last week's huge anti-government protests, the meeting is likely to have started with smiles and handshakes.
However, as soon as Gambari got down to serious business, questioning Senior General Than Shwe about the death of an officially acknowledged 10 people and the arrests of hundreds, if not thousands, the atmosphere may well have got frosty, insiders say.
"Than Shwe can be very charming and friendly when he wants to be," said Razali Ismail, who met him half a dozen times during his five years as Gambari's predecessor as U.N. point man on Myanmar.
"He speaks English quite well and they try to be hospitable when you are there; but they don't like intrusiveness. They don't like you asking about things that they consider to be their internal affairs."
Than Shwe's career started from humble beginnings.
Born in February 1933 in what was then part of the British Raj called Burma, he worked as a postal clerk before joining the army at the age of 20.
Apart from a focus on psychological warfare, little is known about his progress through the ranks of the secretive armed forces that seized power in 1962 and which have maintained a stranglehold on power ever since.
Shortly after the coup and under the aegis of then-dictator Ne Win, he was appointed an instructor at the Central Institute of Political Science before eventually becoming commander of the 88th Light Infantry Division in 1980.
The promotion was a springboard to becoming chairman of the regional committee of the Burma Socialist Program Party (BSPP) -- the core of Ne Win's single-party system that collapsed during a pro-democracy uprising in 1988.
After a series of internal purges -- or "retirement on grounds of ill health", as the generals prefer to call it -- he emerged as unchallenged military supremo in 1992, with the official title "Senior General".
Some of his first public words as leader suggested the army would "not hold onto power for long", igniting hopes of a serious bid to reinstall civilian rule and repair the damage done to the once-promising economy by years of Ne Win's disastrous "Burmese Road to Socialism".
As is so often the case in Myanmar, the optimists were proven wrong. Suu Kyi was to spend most of the interim years in prison or under house arrest and the economy, the rice bowl of Asia at independence from Britain in 1948, slid deeper into the mire.
Than Shwe's personal dislike for Suu Kyi is said to be so intense he walked out of a meeting with a foreign ambassador simply because the envoy uttered her name.
In 2003, Than Shwe's main challenger as paramount leader, the Prime Minister and military intelligence chief Khin Nyunt, was purged, again under the guise of retirement on health grounds.
With the exit of Khin Nyunt, the one general outsiders felt they "could do business with", and the junta's sudden retreat to Naypyidaw, a new capital hewn out of the jungle, Than Shwe's isolation became absolute.
Apart from the annual Army Parade, his one notable public appearance came in the video of his daughter's wedding in 2006, a copy of which was smuggled out of the country and plastered over the Internet.
In a 10-minute clip, the "old man" frequently rumored to be at death's door, walked stiffly at his daughter's side wearing a starched white shirt and an traditional orange wrap at ceremony whose lavishness sparked outrage among the starving masses.
In January, he paid a hush-hush two-week visit to a top Singapore hospital, missing an Independence Day banquet for the first time in 16 years and sparking rumors he was being treated for intestinal cancer.
As events of the last week have illustrated, reports of his imminent demise proved premature.
(Additional reporting by Darren Schuettler)