Nothing to add, really, to the earlier reviews except to clarify some things about the film. The location is never really stated explicitly in the film, except that it is somewhere on the border of 'Red China' where foreigners are safe. In 1967 that is either Hong Kong or Macau. Since there is legal gambling shown going on, it has to be notionally Macau. Except that I cannot detect a single scene shot in Macau. Many of the interiors look like they were done on a European sound stage as well.
All the street signs, for example, have Chinese and English text (= Hong Kong; in Macau it is Chinese and Portuguese.) There are identifiable shooting locations in Hong Kong. The opening train sequence is shot on the Kowloon-Canton Railway tracks somewhere in the vicinity of Taipo. There is a back-projected car ride down Nathan Road, Kowloon, and one can see the wall and gate of St. Andrew's Church for a second or two. Earlier, there's a car ride shot in Wanchai. There are several scenes shots in Aberdeen, and a little booth selling tickets for the "Ap Lei Chau Ferry" (this was before there was a bridge there.) Some of the waterfront/speedboat shots appear to have been done in Clear Water Bay or Sai Kung, probably because of the proximity of the Shaw Brothers Studio which might have offered some advice. Perhaps most amusing is the 'Temple of the Bells' under which the treasure is buried, which is actually the exterior of the Roman Catholic Diocesan Seminary at Wong Chuk Hang! For me it's actually these shots of a run-down but livable Hong Kong in the Vietnam War era that are most interesting, a document that preserves a lot of footage of a place that has now completely disappeared under 20 years of 'Red Chinese' rule.
