As for the .epub guide, I assume you're looking for a comprehensive guide to help you understand the book, possibly for a book club or academic purposes. Here's a general outline:
"El Cuarto Mono" is a Spanish-language novel written by Javier Sierra. The book, which translates to "The Fourth Monkey" in English, is a thriller novel that follows the story of a mysterious figure known as "El Cuarto Mono" (The Fourth Monkey).
The story revolves around the character of José, a former musician who becomes obsessed with a mysterious figure known as "El Cuarto Mono." As José delves deeper into the mystery, he uncovers a series of gruesome murders and cryptic messages that lead him on a thrilling adventure.