For a long time, the people of Hargigo, a village in the tiny African country of Eritrea, were living without enough food for themselves and their animals. Then along came a scientist, Dr Gordon Sato, who helped to change their lives for the better. And it all started by planting some special mangrove trees. This fascinating story of environmental innovation is a celebration of creativity, hard work and the ability of one man to make a positive difference in the lives of many.