If someone would have told me back in the '90s that the way to get Stephen King to finish up the Dark Tower series quickly was to hit him with a minivan, I would have been on my way to Maine to rent a Dodge Caravan before you could say, "Bango Skank was here." 
 I confess this not to do more complaining about the long suffering years waiting on some advancement in the Dark Tower books, but to illustrate how utterly obsessed and frustrated I was with this goddamn series. Then King nearly came to the clearing at the end of the path but instead recovered and cranked out three books like they came off an assembly line to finish the whole thing. Before that, I had pretty much given up hope on ever getting another book, never mind seeing an end to it, and King wasn't doing much to make me change my mind with no news about him even working on another DT book. 
 And then came the minivan. 
 Ka works in mysterious ways.... 
 Wolves of the Calla had a lot of things to accomplish. It needed to get the story rolling again after years of it laying fallow. It needed to set up the end run of the series. It needed to be a satisfying book aside from moving the overall arc forward. And most importantly, it needed to answer the burning question all Dark Tower fans had: Whatever happened to Father Callahan from 'Salem's Lot? Oh, wait. I had never asked that question. Oh, well. I found out anyhow and it turned out to be a pretty good part of the story. 
 Roland and his crew have been moving along the path of the Beam towards the Tower, but they seem to have been in a kind of timeless funk. (One of the things I love about the series is that the decay of the Tower has caused both time and space in Roland's world to become soft and drift. It's also a nice metaphor for the limbo that characters are in between books.) Just before entering the nastiness of End-World, they find Calla Bryn Sturgis, a farming town with a big problem. 
 Almost all the children born in the Calla are twins. Every twenty years or so, dozens of creatures the townsfolk call Wolves come on horseback and steal one from each set of twins. They take those kids back to Thunderclap, a place the gunslingers have already been warned about, and eventually return them as almost mindless husks who grow to jumbo sizes before dying young. Try to fight or hide your kids, and the Wolves kill everyone who resists instead of just taking half the kids. The Wolves will arrive in a month, but some in the Calla want to fight back this time if the gunslingers will help. 
 Roland's group has other problems too. They've been making dream-like excursions to New York in the 1970s and found that the special rose growing in a vacant lot there is in terrible danger. The rose is a key manifestation of the Tower in that world. Roland is convinced that if the rose is destroyed, the Tower falls in his world, too, and there goes your ballgame for all of existence. They have to find a way to get to New York in person and save the rose from those threatening it by protecting the owner of the lot. 
 The gunslingers also meet Callahan, a former Catholic priest last seen in the King-verse fighting vampires in 'Salem's Lot. Callahan has an incredible tale to tell of years spent traveling between worlds and being chased by vampires and other nasty agents of the Crimson King before he wound up in Calla Bryn Sturgis.* Callahan has been hiding an evil object that terrifies him, and he wants Roland to get rid of it by taking it with him when they leave. 
 *(Anyone reading the series who wants some more info about who was chasing Callahan and other bits that come into play here should check out King's 'Low Men in Yellow Coats' story in his 'Hearts in Atlantis' collection.) 
 If they didn't have enough on their plate, Susannah's previous encounter with a demon has left her a little bit pregnant, and her personality is being taken over by the baby's 'mother', Mia. Pregnant women are known for strange food cravings, but let's just say that Mia's are even worse than usual. 
 I love this book partly because it's the one that got the Dark Tower story back on track and set up everything for the end run to the last book. I also love it just because this is Dark Tower at its best for me. It's a mash-up of westerns, fantasy, horror and sci-fi. It's like The Magnificent Seven if Yul Brenner and Steve McQueen had to make multi-dimensional trips and deal with robots and vampires as well as protect the town with their six-guns. 
 Another thing I like about this one is that Eddie, Susannah and Jake are now full-fledged gunslingers and not just apprentices, and King expands on exactly what a gunslinger is. They're not just killers, although they do that pretty damn well. They're also diplomats and protectors of the defenseless. It was fun to see Roland's manipulative political side come out when dealing with the Calla folk. The pregnancy storyline didn't do much for me in this, but it becomes a key driver of the plot of the next book. 
 All in all, this is one of my favorite of the DT books, and it was King's clear statement that he was done screwing around and ready to finish this mother. Too bad it took him nearly getting killed to get it done.