Book excerpt: North Carolina's Triangle region is known for universities, research facilities and politics, but even in such a prosperous, diverse, modern environment, crime helps define the edges. These cases cover several decades of murder, fraud and betrayal. Read about the nation's largest prison escape and a couple of North Carolina's poisoners. From a civil rights-era clash of Old South and New and a suspected Cold War spy to new-tech sleuths and tales of diligent as well as discredited investigators, these stories will keep you entertained and aghast at the dark side of daily life. Crime writer Cathy Pickens explores a collection of headline-grabbing tales that shows the sinister side of the Triangle's cities.