In an alternate timeline, 150 or so years ago, a pair of twins with the last name of Morningstarr arrived in New York. The brilliant pair of siblings transformed the city with their visionary inventions. Electromagnetic trains, automatons, solar panels paving the city streets...they were at the forefront of everything that made the city great. And then they disappeared, leaving behind the Old York Cipher - a massive, cryptic puzzle that leads to...something. A treasure, perhaps? Instructions for a new invention? No one knows for certain. For over a century, the citizens of New York pored over clues, hoping that they might be the one to solve the greatest mystery of their age. 

In the current day, twin siblings Tess and Theo, named for the famous Morningstarrs, have just found out that a wealthy developer has purchased their apartment building. The building in question is one of the few remaining original Morningstarr buildings left in the city. It's truly unique. It once housed the lone heir to the Morningstarr estate, an equally mysterious woman named Ava O'Neal and still has its original elevator - one that can (and often does) move in any direction it pleases. Tess and Theo love their home and so does their neighbor, Jaime Cruz. Unfortunately, the developer has plans to tear their building - and all the other remaining Morningstarr buildings- down to make way for new hi-rises, condos, and other modern disappointments. As the developer's creepy minions begin picking the place apart, Tess, Theo, and Jaime join forces to try their hands at the Cipher. Perhaps the answer will help them to save their homes and the rest of the Morningstarr legacy. 

So begins an epic hunt for answers. Tess, Theo, and Jaime are all tremendously fun characters to follow as they sort through ciphers, puzzles, riddles, and history to find the answers that have eluded experts for over a hundred years. Ruby's version of New York is nothing short of stunning, though it might take some time to wrap one's head around the idea of elevators that move in directions beyond up and down. While the general plot (a massive treasure hunt with life-changing rewards) isn't anything new, the innovative setting and exceptionally well-written characters make it feel fresh and exciting. Overall, The Shadow Cipher is a really fun read for all ages, particularly those that enjoy puzzles, history, and idiosyncratic characters.