Our Agent Tiger (1965)

Louis Rapiere, aka Tiger, is sent to Port-a-Pitre (French Guiana), to supervise the recovery of a treasure from a sunken ship. A group of revolutionaries pirates the ship and steals the treasure, intending to sell it to an international terrorist organization called Orchid. When Tiger arrives there, he demands that the French authorities arrest the revolutionaries, but the police, trying to prevent a general strike, do nothing. Tiger finds himself acting alone in a paralyzed territory--as the revolutionaries incite the people to the general strike anyway--and competing against American, Russian, and German spies. Everybody is very interested in the treasure, a rare mineral with tremendous impact on arms development, now about to fall into the Orchid's clutches.