Whilst exploring a network of caves and pot holes, a rock fall sealed the entrance to the caves with thousands of tonnes of rock and another way out must be found. There is much exploring and travelling to be done in this adventure, items left in the caves by previous explorers might prove useful but then again they might prove to be a burden. There are many other problems that will have to be solved, for instance the life of torch batteries may need considering and underwater survival might be a useful skill.