Mr Mercedes is an excellent book. A factual error about the car. The SL500 is a two seater roadster from Mercedes, not a four door. Additionally it is a V8 and not a V12. I think Mr King was describing the S model and I would guess the 6 liter V12 which I believe goes by the S600 model number. The S class is Mercedes largest sedan, a four door and seems to meet the description in the book.