So, you already know I liked "Doctor Sleep" and I have to say that it is not because I am a rabid Stephen King fan. I am, of course, but I have damn good reasons for liking this book. Firstly, it is a sequel to "The Shining," but it is not about "The Shining." It is about the shining and even more so than its predecessor. When I say that, I mean that we clearly can't go back to The Overlook and spend another novel there, though, in some ways this novel does that. Instead, King explores the namesake of the first book to a much fuller degree than the first time around. This time, we are dragged through the good, bad and ugly aspects of the shining via Danny Torrance (Warning: This is where the spoilers begin), aka Doctor Sleep.
I liked that this sequel does not lean on "The Shining" the way it could have. That was a huge success for King and a complex enough story to pull an immediate and heavily replicative (for lack of an actual word) sequel out of it. Of course, there is a ton of "The Shining" in "Doctor Sleep," but they are two completely different novels. Danny isn't a boy. The antagonist isn't a haunted hotel and there are subplots that could not have existed in the limited space of The Overlook. It's exciting in ways that Stephen King has only become in the past few decades. I mean, how could he have gone all these years writing masterfully without getting subtly better all the time?
For me, everything that King writes feels like it is viewed through 50s colored glasses. I do not know why. Maybe it is King's taste in music, the way he describes people, the cars he prefers to write about, etc. Shoot, I don't even know if he writes about the 50s at all. It is just the way I see it. So, that being said, you will probably meet some characters and places that seem a lot different to you than they did to me when I read "Doctor Sleep," but I think you will like them as much as I did -- even the bad ones.
If you don't have the time and just want to get into this one as soon as possible, don't bother rereading "The Shining." You don't need it. King will remind you of what you need to know and the rest will come or remain hidden. It doesn't matter. You will fall right into step with "Doctor Sleep," either way.