It's hard to describe One Must Die succinctly. As the cover says, it's a steampunk murder mystery. Set in a mansion floating above earth that's filled with robots. And hidden keys. And secret passageways. And, somewhere, a treasure vault.
A whole bunch of strangers are invited to try solving a mystery and finding the treasure in the mansion... and then it turns out they're not all strangers after all. Someone must die before anyone can claim the treasure, and there's a time limit, too. You have to find the correct key to open the vault, and you have to find the vault. Lots of treachery and trickery ensues.
This book is kind of like if you put The Westing Game and Clue and Murder on the Orient Express and Sky Captain and the World of Tomorrow in a blender. It's a fast-paced ride, but never gets too scary or too bloody or too intense. I'll be handing this off to my tween and teens to read now that I've finished it.
Particularly Good Bits: Dread seemed to settle over the large dining room like spider threads, wrapping us too tightly for any chance of escape (p. 50).
If This was a Movie, I Would Rate It: PG-10 for violence, some romantic interludes (all tasteful), and talk about illegitimate children.