The fantastic story of an estranged family, brought together by the death of the so called, "uncle John" to attend to the reading out of his will. Mocking his family, the dead man left his riches to complete strangers and people he had met once...or twice. But, tantalisingly, he did leave with his family the secret to his wealth; a mythical valley of diamonds deep in the Kalahari. The family, grumpy old Henry and his daughter Patricia, the brothers, Earnest and George, their half brother, Michael and their cousin, Sandy take off on a journey to find it. After being warned of the dangers of the journey, as well as the threat of being jailed for illegal prospecting of diamonds, the family splits into teams and heads of to find their treasure. But add a villain and a beautiful woman into the throng and the story takes a dangerous turn.

A great safari had come to Africa to make a movie. It had struggled through the jungle in great ten-ton trucks, equipped with all the advantages of civilization. But now it was halted, almost destroyed by the poisoned arrows of the savage Bansuto tribe. There was no way to return. And ahead lay the strange valley of diamonds, where hairy gorillas lived in their town of London on the Thames, ruled by King Henry the Eighth. Behind them came Tarzan of the Apes with the Golden Lion, seeking the man who might have been his twin brother in looks - though hardly in courage!