In I, Alex Cross, the 16th novel in James Patterson's Alex Cross series, Detective Alex Cross faces the brutal murder of his niece. Consumed by grief, Cross vows to find her killer before he strikes again. The Alex Cross series follows the homicide detective, who has a Ph.D. in psychology, as he hunts criminals, solves murders, and protects his family in the Washington, D.C. ghettos. Condition is Good: This used book shows wear to edges and cover. See photos for condition.