Noble House by James Clavell

The tai-pan, Ian Dunross, struggles to rescue Struan's from the precarious financial position left by his predecessor. To do this, he seeks partnership with an American millionaire, while trying to ward off his arch-rival Quillan Gornt, who seeks to destroy Struan's once and for all. Meanwhile, Chinese communists, Taiwanese nationalists, and Soviet spies illegally vie for influence in Hong Kong while the British government seeks to prevent this. And nobody, it seems, can get anything done without enlisting the aid of Hong Kong's criminal underworld. Other obstacles include water shortages, landslides, bank runs and stock market crashes.
 
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