The Third Deadly Sin Edward X. Delaney Series, Book 4.

Retired cop Edward X. Delaney takes on a female serial killer in this spine-tingling masterwork of suspense by New York Times bestselling author Lawrence Sanders By day, she's a middle-aged secretary no one would look at twice. But by night, dressed in a midnight-black wig, a skin-tight dress, and spike heels, she's hard to miss. Inside her leather shoulder bag are keys, cash, mace, and a Swiss Army knife. She prowls smoky hotel bars for prey. Th...