This is the story of Padre Salas, the most charismatic character from the bestselling novel Hell Calling, which dazzled thousands of readers across the globe, and has recently been adapted for cinema by Luis Endera. In this prequel, we discover what caused Padre Salas' flight from Mexico, leading to his taking refuge in Madrid. We will encounter the terrifying cases of multiple possessions of several girls in towns and villages around Guadalajara (Mexico). This is a novel filled with moments of excitement, tension, and no shortage of fear, guaranteed to captivate all those who love the genre.