Pere Callahan, nicknamed the Old Fella, is the one who tells the villagers about the coming of four Gunslingers.  He is the one that contacts them and asks them to the village to help them fight the Wolves.  Those Wolves are creatures that come every generation or so, and take a half of every twin child -"singletons" are rare in the Calla- to have them returned "roont"a couple of weeks later; horribly altered in body and spirit.  Is it Ka or their sense of duty that makes them abandon the path of the Beam, to see if they can help the Calla, and if the Calla wants them to help?  Probably Ka, since Pere Callahan has a little something hidden in his church that is the big brother of the pink glass ball Roland told his Ka-Tet about in Wizard and Glass, and the more the Pere tells about his roamings before reaching the Calla and some peace of mind the more Roland and his friends are convinced that their Ka-Tet is about to expand.

During a few todash sessions, where some or all of Roland's Ka-Tet visit New York in another world, but aren't really physically there, it becomes clear that the rose noticed by Jake before he came to Roland's world might be another manifestation of the Dark Tower itself, and that the Tower's fate is interconnected with that of the rose.  What becomes clear too is that some nasty guys, undoubtedly working unknowingly for the Crimson King, would do a lot to get the vacant lot where the rose grows into their hands.  Eddie, with the help of what was hidden in Pere Callahan's church, goes to New York to convince the current owner that it would be safer for him to go in hiding.  And it takes a lot of convincing to let the stubborn man see the inevitable.

And to make everything a little more complicated Susannah is pregnant, but not from Eddie, and an alter ego is waiting inside her to take control when the chap is about to come.  And the Wolves?  The day their arrival is predicted comes near, will only four Gunslingers, one of which pregnant and with a lurking personality waiting, and three guns be able to stop at least sixty of them?

This is "The Dark Tower V", and it makes no longer sense to try to give a resume of what happened, it would turn out to be a novella in itself.  So if you haven't read the other Dark Towers and expect to jump in in the middle and get everything - fuhgettaboutit.  Not that the story can't stand on its own, far from that, but there's so much you need to know about Jake and how Roland betrayed him once, what happened to him before he came again to Roland's world, what needed to be done to help him come to Roland's world.  You need to know about Eddie and his previous life, you need to know who Susannah was formed out of, and you need to know about the magic involving the glass balls.  A little imagination can help, but only a little.  But then again, would you start with the third book of Lord of the Rings, or the fourth of Dune?  Probably not.

The storyline is quite complex, or rather, four of them are intertwined.  There's Pere Callahan (last seen in Salem's Lot) who tells his story, and of course there are the preparations to deal with the wolves.  But there's also the danger threatening the rose in New York and the bookshop-owner who may hold the key to its rescue, and the dark menace growing inside Susannah may become the first real test for the Ka-Tet, in many ways.  Callahan's bit is the weakest of these four, it seems to be used only to explain what he's doing there but it doesn't really contribute to the whole.  As far as I'm concerned his bit ought to be shortened a little.  But since he talks about his encounters with the Low Men I can imagine the people who haven't read Hearts in Atlantis need a little introduction, but to me that's the only reason he merits this many pages.
The other story-lines are just great; mostly I enjoyed my encounter with the Calla.  It was as if I had been there, as if I knew the place.  King at his best makes people come alive with only a minimal description, and it felt that if I would ever meet one, I'd recognize him.  The same goes for Calvin Tower, the bookshop-owner.
Together they form a nice blend where some doom constantly simmers in the background.  Jake having to take the first real adult decisions in his life, requiring him to say good-bye to his youth forever.  Roland needing to keep a secret for his Ka-Tet.  The threat of the wolves, the threat against the rose.  And the threat growing inside Susannah.  All that darkness is hidden behind the beautiful picture of a happy community living in a lovely area, at the end of the summer.

King has a reputation for building up a great climax and then not being able to properly finish the story.  In this case I would say it's quite the contrary.  The Wolves' story is just the coathanger for a lot of things that are going on and that seem to be leading into different directions, and about halfway through the book I wondered where everything would lead to.  Maybe I should trust Ka a little more :-)  Everything leads to a decent finale, and with a more than decent cliff-hanger - of course.