Deeba and her best friend Zanna live in London. They are mystified when strange attention begins to find Zanna. Foxes and dogs start following her around and quietly gazing at her. Messages are left for her and a stranger hands her a ticket she can not decipher. One night they observe an umbrella sneaking around her window and they follow its crabish scampering down an alley. They end up in a basement that whisks them to another world freakishly named Un London. Un Lun Dun - London on an acid trip. Trash is animated and housed are built out of abandoned junk seeping through from our world. Crazily enough, they've been waiting for Zanna to come and save their world. She is immediately recognized as the "Shwazzy" or the Chosen One.
Unfortunately she is not up for the task. The evil Smog, which is seeking to take over Un Lun Don, and then the universe, easily knocks her out. Deeba is able to bring her back to London and heal her, leaving Un Lun Dun to growing war. Deeba is not able to forget her friends there and finds evidence that the man they thought was going to lead them is in fact a traitor. She returns to set things right and is drawn into the struggle.
It turns out that the Swazzy was not their best hope. Deeba's courage, common sense and ingenuity bring her to become the true heroine. Time and again she gets in a tight spot that seems to have no escape only to come up with something unexpected and brilliant that turns the situation around and defeats her enemy. Although she repeatedly refuses to accept the role of savior, she keeps revealing a unique brilliance that perfectly out-thinks the evil threatening her and her friends. The constant plot twists and up and down action are full of delightful surprises revealing Deeba's humble, never-outdone creativity and persistence.
I have to say the most satisfying, entertaining part of the book for me is the extremely clever use of language. As I said, everything in Un Lun Dun is freaked-out. The trash is animated so one of Deeba's companions is a milk carton that follows her around like a pet. There is a book that speaks prophesies and becomes depressed when it turns out he's wrong about the Swazzy. The leaders call themselves the Propheseers and keep and office on a moving bridge called the Pons Absconditus. It is guarded by living trash cans called the Binja, who fight with martial arts-like intensity. The moon is shaped like a peppermint lifesaver, with a hole in the middle, and is called the Loon. One of Deeba's new best friends is a half-ghost boy called Hemi. They go on a quest to find a weapon called an Ungun. The only thing their enemy The Smog is afraid of is "the Ungun and nothing". Every time you think you have figured out what is going to happen next the whole thing turns upside down - but it all makes perfect sense with a dream-like logic.
The second time Deeba goes to Un Lun Dun she tries to enter by climbing the shelves in a library. She is not sure but she thinks, from following a clue on a scrap of paper, that the books will lead her into the other side. She climbs for a long time and the shelves continue to stretch above her. At last she reaches the top of an enormous tower.
"It was a cylinder, at least a hundred feet in diameter, hollow and book-lined. Outside, bricks went down the height of countless floors past small clouds and flocking bats, to UnLondon's streets. Inside, it was ringed with the bookshelves she had climbed. [...]
There was motion below her. There were people on the shelves. The clung to the edges of the cases and moved across them in expert scuttles. They wore ropes and hooks and carried picks on which they sometimes hung. Dangling from straps they carried notebooks, pens, magnifying glasses, ink pads, and stamps. [...]
"Can I help you?" the woman said. "I think there's been some mistake. How did you get past reception? These shelves aren't open-access."
"Sorry," said Deeba. "I don't know what you mean."
The woman moved like a spider just below her. She looked at Deeba over the top of her glasses.
"You're supposed to put in a request at the front desk, and one of us'll fetch whatever you're after," she said. "I'm going to have to ask you to go back." She pointed over at UnLondon.
"That's where I want to go," Deeba said, pulling off the glove and putting it in her bag. "But I came from inside."
"Wait... really?" the woman said excitedly. "You're a traveler? You came by storyladder? My goodness. It's been years since we've had an explorer. It's not an easy journey, after all. Still, you know what they say: 'All bookshelves lead to the Wordhoard Pit.' And here you are.
"I'm Margarita Staples." She bowed in her harness. "Extreme librarian. Bookaneer."
Unfortunately while Deeba was back in London things went from bad to worse in UnLondon. She has come back to tell them what she knows; she ends up leading a small group of rebels that accept her knowledge and throw their lot in with her quest. The book culminates in a giant battle for the control of UnLondon against the deadly cloud of Smog. The action is wild and and there are casualties on both sides.
I really loved this book and I think anyone who likes fantasy and action will enjoy it. Highly recommended for grades 4 and up. At Random House you can read an interview with the author, get a teacher's guide and read an except.