The Incredible Petrified World

At a gathering of California scientists, Dr. Methany debates with his colleagues about his latest research project, a $70,000 underwater bell that will explore the ocean floor, penetrating deeper than any diver or marine equipment has gone before. Meanwhile on a boat off the coast of Florida, prestigious oceanographer Dr. Wyman oversees a similar bell expedition to the ocean floor. As his crew, scientists Craig Randall and Paul Whitmore, science student Laurie and female reporter Dale Marshall, begin their descent in the cramped quarters of the bell, Craig maintains radio contact with Wyman. However, as the bell passes 1,700 feet, the cable breaks and the radio goes silent. Without another bell capable of reaching such depths, Wyman immediately gives up hope of rescuing his crew and tells a reporter that he does not know the reason for the mechanical failure. Meanwhile, the bell safely lands on the ocean floor. Although the crew is upset about their dilemma, Craig establishes that their oxygen supply, while limited, is still intact, thus securing their immediate survival. Looking out the bell porthole, the crew is surprised to be able to see a rocky landscape outside. Knowing that the actual ocean floor is so far from the sun that no light can penetrate it, the scientists deduce that they are at a much shallower depth and thus will be able to scuba dive. After shutting off the oxygen to reserve the supply in the bell, the crew exits the hatch in wetsuits and explores the area. Meanwhile aboard Wyman's boat, sonar operator Wilson reports movement on the screen, but Wyman believes the sonar is merely reading the crews' corpses slowly floating to the surface, assuming they were killed instantly by the intense pressure at the ocean floor. In the water, Craig, Paul, Dale and Laurie find a cave filled with breathable oxygen and lit by phosphorous rocks lining its walls. After briefly exploring the cavern passages, Craig and Paul return to the bell to collect supplies, hoping that they can survive in the cave until they find a passage that will lead them to the surface. On the surface above, Wyman continues to ignore Wilson's suggestion that the bodies continuing to move down below are not floating but living humans moving in and out of the bell. Back in the cave, after they cook the fish they have speared for the group, Paul asks Craig about their chances for survival. Craig is cautious, stating that the air in the cave might not be coming from the surface but some other source. The next day the group explores numerous cavern passages until they find a small pool of fresh water. While they rest, Dale reads and then tosses out a note from her lover. When Laurie jokes that she should keep it, as there is nothing else to read, Dale retorts that Laurie should leave her alone, suggesting that as women, they have nothing in common except competition for the men's attention. Soon after, Craig realizes that the compass is not working because of magnetized rock, so Paul suggests that they mark their path by breaking off stalagmites and laments that they did not attach a message to a high-pressure tank and send it to the surface. With growing pessimism, Craig announces that it is better that Wyman does not know about their survival, because no one will be able to save them at such depths. Paul, however, maintains his confidence that the resourceful and experienced Craig will manage their return to the surface. Continuing on, the group suddenly finds a human skeleton and a bedraggled, bearded old man, who explains that he found the cave when his ship sank twelve years ago. The skeleton is the remains of the only other survivor. The old man insists that there is no way out of the cavern, explaining that the air is not from the surface but from a volcano deep in the cave. Paul and Craig follow the old man to the volcano and return to tell the women that the volcano is responsible for their air and mostly likely there is no passage to the surface. Craig takes the despondent Laurie in his arms and professes that he has always loved her. When she shares her love in return, Craig reminds her that they are fortunate to have each other to share their isolated life below the surface. Meanwhile, Wyman travels to California to convince Methany to launch his bell expedition, which was canceled after Wyman's failure. He explains that the design problem was that the bell was not made to accommodate pressure coming upward from the ocean floor, only the pressure of the descent, and that the couplings holding the cables were probably ripped off as the bell drew close to the bottom. After Methany agrees to dive at the same Florida site, Wyman and his brother, who has been working for Methany, redesign the bell. Days later Craig and Paul return to the bell for supplies and find Wyman's brother waiting for them, having successfully led the second bell's descent to the ocean floor. Meanwhile back in the cave, after Dale bitterly mocks her for following Craig's orders, Laurie finally realizes that Dale is jealous of her relationship with Craig. Suddenly the old man corners Dale and lasciviously suggests that she remain with him, while he kills the others. When Dale screams for help, the volcano suddenly erupts and an avalanche of rocks kills the old man. Rushing to escape the falling debris and molten lava, Dale and Laurie reach the mouth of the cave where they find Craig, who gives them portable respirators and orders them to follow him back to the bell. Later, as they ascend in the second bell, Craig radios Wyman to report everyone's survival, while Dale apologizes to Laurie for her jealous behavior. When they are safely back on the boat and heading for land, Craig rejoices in having "room to breathe."