Immediately below is the cover of The Shadow of the World-Famous Nine, which was done by Chloe Bristol. The other illustrations further below, which come from the inside of the book, were done by Kristina Kister. All of the illustrations exist under copyright of Chloe Briston/Kristina Kister/Christy Ottaviano Books/Hachette.

Here is the overview of The Shadow of the World-Famous Nine that can be found on the back of the book:

Summer is in full swing at The Number Nine Plaza, the world’s largest and most fabulous department store, and best friends Zander and Natasha are looking forward to weeks of discovery after thwarting the vengeful Darkbloom’s attempt to destroy The Nine. But has the danger truly passed? Store employees begin acting oddly, a long-lost clue to an ancient store mystery is uncovered, and Zander and Natasha themselves become targets for attack. When a devastating magic spell places The Nine under new peril, the two friends find themselves in a race against the clock to solve the store’s ever-deepening riddles and preserve the world-famous Number Nine Plaza from destruction.

Here are some pictures from the book: