Unbreakable

What happens when you put two complete strangers - sans clothes - in some of the most extreme environments on Earth? Each male-female duo is left with no food, no water, no clothes, and only one survival item each as they attempt to survive on their own.

A group of the best survival experts in the world take on an un-survivable situation: 40 days. 40 nights. No food, water or clothes. To survive they'll need to master the environment, pushing far beyond the breaking point. Will even one be able to finish?

MegaStructures is a documentary television series appearing on the National Geographic Channel in the United States and the United Kingdom, Channel 5 in the United Kingdom, France 5 in France, and 7mate in Australia. Each episode is an educational look of varying depth into the construction, operation, and staffing of various structures or construction projects, but not ordinary construction products. Generally containing interviews with designers and project managers, it presents the problems of construction and the methodology or techniques used to overcome obstacles. In some cases this involved the development of new materials or products that are now in general use within the construction industry. MegaStructures focuses on constructions that are extreme; in the sense that they are the biggest, tallest, longest, or deepest in the world. Alternatively, a project may appear if it had an element of novelty or are a world first. This type of project is known as a Megaproject.

Family Liaison Officer Lisa Armstrong becomes a little too emotionally involved with a case (to the point where she might compromise it) concerning a pair of missing Morecambe twins to whose distraught parents she is assigned.