The Wastelands begins a few months after the events culminating The Drawing of the Three took place. Both Eddie and the newly merged Suzannah are learning gunslinging abilities, and both are learning not only to escape their pasts but use them to their advantage. Eddie has taken up an old childhood hobby, whittling, and they are about to resume their quest for the Tower. However, one thing is greatly impairing their forward movement: the fact that Roland the gunslinger is losing his mind.
The reader, being omnipresent, undertstands thi turn of events, but it takes the characters a little longer to grasp: when Roland saved Jake in DT2, unable to "let him fall" again, he created a paradox: Jake is alive in his world, but if that is so, the events of the first book, The Gunslinger could never have taken place. The first half of this long book details the division of both Roland and Jake, and their deadly struggle for answers and hope. Jake eventually does make it into Roland's world, but only through several intense sequences (including a vision quite like Roland's at the end of book 1), ending in a darkly horrific struggle within the body of evil itself.
The second half propells the pilgrims a long way in their travels. They discover that anything that happens in the present can be keys to future puzzles, (one of the series' greatest achievements is fleshing out events which at one glance seem to be coincidental, but are not). Things like the purple blade of grass, Eddie and Jake's shared dreams, Suzannah's psychic flashes, or the very existance of Jake's books (not to mention the probability that the book belonged to each of the New Yorkers at one time) are just the most obvious examples. We learn a bit about Roland's past in his recounting of the fair day riddling. Then, the city of Lud.
The party is seperated at this important cross in their quest, and Jake is kidnapped. Roland, bound by his promise that he will not let the boy die again, goes after him. Eddie and Suzannah go forth to locate Blaine, the train they know of from prophecy which will take them through "The Wastelands." All three from our world are tested on both their gunslinging and mediating abilities, and thus propel themselves ffurther on in the understaning of the philisophical questions of ka, khef, and ka-tet.
After several frightful sequences involving the inhabitants of Lud (including that of a man(?) we have all seen before, one who goes by the initials R.F.), the party rejoins in the body of Blaine the Mono. The only problem with that is Blaine is insane, Blaine is suicidal, and Blaine really likes riddles.
Thus ends this part of The Dark Tower. Come November, we'll learn much more about Blaine and the Tick Tock man, et al. I know I can't wait.