My first (and probably last) Stephen King novel! And that is mainly because this one was not scary. The premise is that Jake, a teacher in his 30s, finds a portal in a local diner that goes back to 1959. Every time he goes back, he arrives on the same day at the same time. Each trip is a complete re-set and only takes him a minute, no matter how long he stays in the past. Jake learns that he can change things in the past and affect the future. He decides to go back in time to stop Lee Harvey Oswald from shooting JFK in 1963, a task that will mean living in the past for four years.
I liked the book overall. It was an interesting premise and Stephen King is a good writer. My complaint was the length. The book was 800 pages and did not need to be that long. It languished in the middle when you just want it to hurry up and get to 1963 already. But if you are interested in JFK and don't mind a long book, this is a good one.