You can find the version of Dan Brown's Digital Fortress through several legitimate digital library and retail platforms. Where to Find the EPUB Public Libraries

The novel introduces us to Susan Fletcher, a brilliant cryptographer working for the National Security Agency (NSA). Unlike Brown’s later male protagonists who traverse physical cities, Susan’s journey is largely intellectual and confined to the high-tech walls of the NSA’s headquarters. However, the stakes are no less dire.

The EPUB version of this standalone novel can be purchased at Apple Books or eBooks.com . Digital Fortress - Dan Brown - Apple Books

: Official editions are often listed on publisher sites like Penguin Books Book Overview