The story:
An Explorers' Club member is boasting to his colleagues about a drinking cup made out of a single diamond once belonging to Alexander the Great but now owned by a ???phantom??. He is not believed, but a shifty sea captain immediately sees a golden opportunity to make money through a con game.

As the Phantom returns from Keela-Wee (see S080 The Beach), tom-tom drums reveal that a man is calling for him in the jungle. It proves to be our distressed member with a furious sea captain in hot pursuit. The stage is set for a tense conclusion in the Phantom's big treasure room...