In 2006, twenty-seven-year-old Jessica Buchanan stepped off a plane in Nairobi, Kenya, with a teaching degree and long-held dreams of helping to educate African children. By 2009, she had met and married a native Swede named Erik Landemalm, who worked to coordinate humanitarian aid with authorities in Africa. Together the two moved from Nairobi to Somalia, and with hopes of starting a family, their future couldn't have been brighter. . . .

But on October 25, 2011, Jessica and a colleague were kidnapped at gunpoint and held for ransom by a...