Nairobi, Jan. 9 -- One evening in July last year, John Ngumi showed up at a high-profile dinner party at a city hotel to the surprise and delight of everyone. Jaws dropped and attention shifted to him.

This was the same month he had been appointed to chair the board of Safaricom PLC.

Wearing a maroon sweater, a light blue shirt and an air of poise, Mr Ngumi seemed to gel among the guests.

He made a toast, had a brief chat with the hostess and left almost stealthily.

For most of his life, the man has been a member of high society and a citadel of power, influence and wealth.

His father was a senior officer in President Jomo Kenyatta's government. ''My father had immense wealth. We did not know what work he did,'' he says.

Describing ...