Mile 81 got its title from a closed down rest stop where a strange and very muddy car pulls over and just park there. No one's getting out and not much of anything is happening. Until someone stops and investigates the car that is. Those who do quickly learn that it's the last thing they'll ever do. You see, the muddy car isn't a car at all. It's never explained what it is but it's definitely not a car, of that you can be certain.
As usually King paints character portraits like no one else and for most of the time it works here. I say most of the time because King introduces us to Rachel (6 years old) and Blake (four years old) in the story and in my opinion King made them way to young based on what they say and do. And it's really nothing wrong in what they say and do but I think they are more like ten and eight than six and four and it annoyed me a bit.
Still though, I enjoyed Mile 81 and the book could easily have been longer. I would have loved to know more about the car, more about the characters and specially more about the persons that was consumed by the car. What happened to them? Are they gone forever? Probably but then again, you never know when it's King holding the pen.