The main protagonist of "Doctor Sleep" is Danny Torrance, son of Jack. As a child he used to be a quiet, introverted boy. He also had the special "gift", referred to as shining. He tries very hard not to follow in his father's footsteps but he learns that escaping from your past and striving to be someone else that your father ended up being is not that easy. Similarly to Jack, Dan struggles with problems with alcohol and drugs. He is unable to find a place for himself and wanders without purpose. That is the case until he finds a job in a nursing home, where he can finally put his talent into good use helping the elder patients in their final moments. He becomes known as doctor Sleep. Dan's story is interwoven with that of Abra Stone, a girl who grows up discovering and trying to understand her great talent (shining as well but on a much larger scale). The two protagonists establish a telepathic relationship. We soon learn that Abra is in danger of "The True Knot", a group of ancient vampire-like creatures that feed on the shining. In order to consume it, they kidnap, torture and kill children who possess it.
I think that "Doctor Sleep" is the best King's book about dying since "Insomnia". I really liked the way he described the final moments of patients of the nursing home Dan works in. There's depth and some interesting imagery in these descriptions. These descriptions are quite powerful with all the vivid memories that Dan experiences with his patients but sadness is not a dominant feeling there. I also liked the way King shows how difficult it is to avoid your genetic and mental heritage. The antagonists are also presented in an interesting way. They're not just superhuman beings of unlimited power - they have their own problems, both physical and emotional. It makes them a bit more human but at the same time I never felt that what they do can be justified in any way. Also, Dan Torrent is an interesting character as he often acts in a selfish, sometimes even immoral way but it's not that easy to actually judge him, knowing his past and the way his father traumatized his early years. For me, this moral ambiguity was one of the novel's greatest strengths. Overall, it's a very solid read. You don't need to read "The Shining" to enjoy "Doctor Sleep" but it definitely helps. 4+/6
EDIT: I chose this cover as I like the subtlety in it. It also shows the cat that wasn't perhaps significant for the plot but he had an important function as he would always pay a brief visit to those about to pass away in the nursing home.