A geologist without personal fortune, Cyprien Mere has no hope of marrying Alice Walker, daughter of the owner of the richest diamond mine in South Africa. Despite the hostility of the miners in the region, our scientist creates an artificial diamond, the Southern Star, immediately stolen by greedy hands. Alice's father promises his daughter's hand to anyone who finds the thief and the diamond. For Cyprien, a race against time against dangerous rivals enters the Veldt.