The Reptiles: Turtles and Tortoises is a PBS Nature documentary narrated by Howard McGillin, taking a close look at ancient creatures marching slowly through the millennia. A turtle’s shell is among the most peculiar but successful pieces of design in the natural world. Unchanged for 200 million years, it has allowed the various species of turtles to populate almost everywhere in the world. But the limitations of life in a shell are causing turtles problems in today’s world. Over exploitation by humans has caused many turtle species to become extinct or endangered. This episode introduces some inspirational people who are trying to help them.