Nine surviving members of a U-boat crew captured during World War II gather in North Carolina for their 60th reunion, only to find themselves targets for a group kill. Meanwhile, after scouring hospital records to find her biological parents, a 36 year-old unwed mother from Oklahoma stumbles upon an obscure family connection to the murders. Carolyn Baker unknowingly holds the clue that could solve the crime, explain her own past, and expose long-concealed secrets. As she thrusts herself into the FBI investigation, the killer's plan shifts....