Wolfgang Stolzenberg has two main companies in his portfolio: Castor Holdings, a Canadian mortgage finance concern, and Imry, the private, London-based property developer. Mr Stolzenberg, who doggedly shuns publicity, is chairman of both.
At the end of a recent creditors' meeting in a Montreal hotel, he fled through a back door to avoid waiting reporters and photographers.
Castor has been forced into bankruptcy with debts of Cdollars 1.4bn (pounds 600m). Century Asset Management, another separate British company controlled by Mr Stolzenberg, has also gone under.
Barclays Bank, which is owed pounds 440m by Imry, must be hoping the major British part of Mr Stolzenberg's empire does not also suffer the same fate.
Imry specialises in prestigious commercial projects. It was the developer of the Royal Mint building at Tower Hill in the City, Islington Green in north London and the Rose Theatre site. It was also Alan Bond's original partner in the St George's hospital redevelopment at Hyde Park Corner.
Mr Stolzenberg was part of a group - other members included Eagle Star and Prudential- Bache - that acquired Imry for pounds 314m from its founders, Martin Landau, the deputy chairman, and Martin Myers, the chief executive, in 1989. Mr Landau has since left.
Last year, the collapse of the property market saw Imry undertake a refinancing by Barclays and the seizure of control by Mr Stolzenberg. His co- investors were bought out for a fraction of their original investment. Barclays doubled its exposure to the company by granting a further pounds 200m loan.
Little is known about Mr Stolzenberg. He is 53, lives in Belgravia and Montreal, and until recently criss-crossed the Atlantic on a dollars 22m executive jet leased from a Swiss bank.
Tall and immaculately- dressed, he used to work for Dresdner, the German bank in Frankfurt. He came to Britain and set up his own property and venture capital operations.
Last March, Castor stunned the Quebec financial community by suddenly applying for a court order seeking protection from creditors for 120 days. Developers defaulting on second and third mortgages were blamed for the move. Castor specialised in collecting funds from banks and other investors and then making loans to property developers in Canada and the US.
Castor has since collapsed.