From the Flap:

All good things must come to an end, Constant Reader, and not even Stephen King can make a story that goes on forever. The tale of Roland Deschain's relentless quest for the Dark Tower has, the author fears, sorely tried the patience of those who have followed it from its earliest chapters. But attend to it a little longer, if it pleases you, for this volume is the last, and often the last things are best.

Roland's ka-tet remains intact, though scattered over wheres and whens. Susannah-Mia has been carried from the Dixie Pig (in the summer of 1999) to a birthing room--really a chamber of horrors--in Thunderclap's Fedic; Jake and Father Callahan, with Oy between them, have entered the restaurant on Lex and Sixty-first with weapons drawn, little knowing how numerous and noxious are their foes. Roland and Eddie are with John Cullum in Maine, in 1977, looking for the site on Turtleback Lane where "walk-ins" have been often seen. They want desperately to get back to the others, to Susannah especially, and yet they have come to realize that the world they need to escape is the only one that matters.

Thus the book opens, like a door to the uttermost reaches of Stephen King's imagination. You've come this far. Come a little farther. Come all the way. The sound you hear may be the slamming of the door behind you. Welcome to The Dark Tower.