This dissertation focuses on the study of Western esotericism in European culture and forms a method of discovering esoteric topics in cultural artifacts. Using the definition as a corpus of knowledge historically divided between esoteric, reserved for the intellectual and power elite, and exoteric, available for everybody, I argue that esotericism represents the knowledge that always accompanied the cultural production of the Mediterranean zone, adding a spiritual meaning to any visual or written work of art. The contemporary novels of the past decade by the Spanish author Javier Sierra are fully based on a historical investigation, in which esotericism appears as a nuclear topic, revealing the great interest of the public in the mysteries of the past. Through the postmodern cultural theories, together with sociological and historical methods, the dissertation explores the cultural processes that lead to the shift of esoteric knowledge in the 20th century from secretive to publically available. The study defines the purpose of recreating the European past and investigates the secrets of European cultural formation. Through an insider-outsider perspective, it analyzes the cultural artifacts, that appear in the novels in the form of reference or as a nuclear part of the plot. It presents the scope of esoteric currents, that are divided between the discipline of religion, science, and philosophy, which form the tetrahedron of knowledge as a theoretic model for this study. The constructed model reveals the interaction of the three disciplines throughout the history and examines the reasons for the religious disenchantment of the 20th century, proven through Digital Humanities’ research as the predominance of science over the Catholic Church, which allowed the esoteric knowledge to reappear. The study explores the affiliation of esotericism with science through the scientific-cultural inquiries between the ancient myths and reality, by showing that man’s consciousness had always been dependent on the scientific perception of the world. It explores the pagan symbolism that is mixed with Christian traditions and reveals the stories, hidden behind the representation of the greatest works of art, by combining and analyzing the wisdom of the past and the contemporary spiritual inquiries in their philosophical meaning.