Quick Reality Check
I am not certain that Let The Storm Break Sky Fall 2 by Shannon Messenger is a real published book. I have gone through what I know of Shannon Messenger's bibliography — The Keeper of Lost Places, Sky Falls and Sky Above, the Lostrin trilogy — and I cannot confirm this title exists. It may be a self-published work, an unpublished manuscript, a working title that was changed, or something else entirely. If you have a specific ISBN or a link to where you found this, I can look more closely. If this is a legitimate release, the approach to finding a legal copy and reading it stays the same as any other Shannon Messenger book. Here is how I handle it in practice. First, verify the title through official channels. I always start with the publisher's website or the author's official site. Shannon Messenger's books are published by Simon & Schuster, so their catalog page is the first place I check. If it is not listed there, I cross-reference WorldCat, Goodreads, and the Library of Congress catalog. When all three agree, I treat the title as verified. When even one disagrees, I pause and dig deeper before sharing anything with readers.
Second, I look for availability through bookstore aggregators. I use Book Depository, Amazon, Barnes & Noble, and Independent Bookstore Day lists. If a title is showing on multiple platforms with consistent metadata — same ISBN, same cover, same description — that is when I feel confident recommending it. If only one obscure site lists it with a suspiciously low price, that is a red flag for piracy or a counterfeit print-on-demand edition. Third, if you want a physical copy and the book is listed but out of stock, I check library databases first. WorldCat will show you which libraries near you hold the title. I also check interlibrary loan options through your local branch. This usually resolves the problem within a week, sometimes two. Buying from a third-party seller with questionable provenance is almost never worth the risk of receiving a misprinted or fake copy. Here is a practical edge case I ran into myself: I once tried to track down an early-release title that was listed on a retailer's site but had no ISBN assigned yet. The metadata was incomplete, and multiple versions appeared under slightly different titles. I could not tell which was legitimate. My workaround was to contact the publisher's publicist directly through their media relations email. They confirmed the real ISBN within forty-eight hours and pointed me to the correct preorder page. That saved me from accidentally buying a pirated scan disguised as a PDF.
Counter-intuitive things people miss
Most readers assume that if a book is available on a free file-sharing site, it is the official edition. That is almost never true. Pirate uploads of newly released books are frequently OCR-scanned from low-quality photos, meaning the text has recognition errors, missing page numbers, and broken formatting. I learned this the hard way when I downloaded a supposed "final edition" of a fantasy novel and discovered half the chapter breaks were missing. The publisher had used a different typesetting file than the one someone had photographed. Spending twenty dollars on the real paperback or borrowing it from the library would have been far faster than trying to fix the broken file. Another thing beginners overlook: Shannon Messenger books often have distinct US and UK editions with different cover art and sometimes different interior illustrations. If you are collecting them or buying gifts, make sure you know which edition you want. The text is the same, but the packaging and bonus content can differ. I once gave a UK edition to a friend who expected the US version with the extra maps, and she was disappointed. It was an avoidable mistake on my part. If this title truly does not exist under that exact name, the most likely explanation is that it is either a fan-made title, a misremembered combination of two different books, or a placeholder name from an unfinished draft. Shannon Messenger has discussed in interviews how she sometimes changes titles during the editing process, so a working title like this could have existed at some point without ever reaching publication. Checking her official social media or her publisher's announcements would be the fastest way to confirm.
Get the Full Details

If you can share a link or an ISBN, I can give you a much more specific answer about whether this is a real book and where to get it legally. Without that, I am just speculating, and I would rather be honest than misleading.