On what was probably the coldest morning of the year (2009), seven endangered whooping cranes- guided by four ultralite aircraft- completed their migration to the St. Marks Wildlife Refuge in North Florida. A production crew from WFSU-TV arrived at a field in St. Marks before dawn, where they waited with 2,000 enthusiastic onlookers to see the cranes fly overhead en route to their isolated pen deep within the refuge. This is the story of these animals' journey, and of the people who have dedicated their lives to keeping them from going extinct.