This fantastical tale tells the story of Zanna and Deeba, who live in a housing project in London. One day, an umbrella leads the pair "down the rabbit hole" to Un Lun Dun, an alternate version of their city where trash cans and milk cartons come to life. Soon, Zanna finds out that the residents of Un Lun Dun believe her to be "the chosen one" who is prophesized to save their city from the evil Smog that threatens their city.