Rod Slater is appointed general manager of a gold mine in South Africa. Barely in the job, his superior, Manfred Steyner, pressures him into an extremely risky drilling operation. Steyner presents Slater with a forged report claiming that behind a layer of green-stone - the so-called dam - there is gold, not water. Slater has no choice - if he wants to keep his job, he has to go along with it. What he doesn't suspect is that Steyner is involved in stock market speculation and is counting on the dam breaking during the drilling and flooding the mine, so that a shortage will drive up the price of gold. At the same time, Slater falls in love with Terry, Steyner's wife. While the lovers spend a few days in a remote hunting cabin, Steyner secretly has the drilling continued so that Slater cannot trigger the safety mechanism he had installed to protect against a water breach. And so begins a race against time for Slater to return to the mine in time and save the lives of the workers trapped underground in the flooded tunnels. Steyner, who has faked a trip, watches the events unfold from a hillside.