An engrossing, creepy, very well plotted historical fiction novel about an English teacher who finds a wormhole into the past and decides he’s going to prevent the assassination of John F. Kennedy. The past “has a way of harmonizing,” though, of protecting itself against interference, and the way this story plays out is just ingenious.

I was occasionally confused by what I now know are references to King’s other work (like extended scenes in the town of Derry) but readers more familiar with him will probably appreciate those references.