Saving Grace - Bis dein Tod uns scheidet

The way the characters manipulate and deceive each other was chilling and compelling. I'm curious what motivated the author to explore these darker aspects of human nature.

The tension kept building but I felt some parts dragged. Was that intentional to build suspense, or could it have been tighter?

Switching viewpoints added layers to the mystery, but I wonder if that was planned from the start or evolved during writing.