In the heart of Gorongosa National Park, Mozambique, the waters of Lake Urema explode with the thrashing of a giant crocodile tail. Gorongosa was once known as the place where Noah left his ark: 1,500 square miles of lush floodplains in central Mozambique, packed with wild animals. All around, enormous buffalo, soaring fish eagles, and countless antelopes roam freely. But on closer look, something strange is going on. Fifteen years of civil war has taken a heavy toll and many species have been almost completely wiped out. All the usual top predators and prey are virtually missing, except for one - giant crocodiles and thousands of them. Discover what is being done to bring this African oasis back to its former glory, including perhaps the most ambitious restoration effort ever attempted, with elephants, hippos and scores of zebra, wildebeest, impala and buffalo, being relocated into the park.

• National Geographic
• Keith David