It is a sultry Sunday evening in mid-February in Siem Reap, Cambodia, in the historic Art Deco Raffles Grand Hotel D’Angkor. In an otherwise peaceful and hushed bar area frequented over the years by guests such as Charlie Chaplin, Charles De Gaulle and Jackie Kennedy Onassis, Anthony Pratt is singing Beatles songs to Gina Rinehart.

Pratt, as is his habit at many functions, breaks into the first few [...]