Before I ever sat down to write The Last Thing She Saw, I visited New Orleans with my husband and my sisters-in-law. One destination was non-negotiable. Algiers Point.   We spent time walking its quiet streets, taking in the historic homes, watching the Mississippi River roll by, and soaking up the atmosphere. Standing there, it wasn’t hard to imagine that history still lingered around every corner. That’s where many of the ideas for The Last Thing She Saw were born. Back home, I dove…