59 pages 1-hour read

The Secret of Secrets

Fiction | Novel | Adult | Published in 2025

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Background

Series Context: Robert Langdon

The Secret of Secrets is the sixth book in the Robert Langdon series of novels by American author Dan Brown, which follows the global adventures of Harvard symbologist Robert Langdon. The series blends contemporary suspense fiction with extended explorations of history, religion, and science, often set against the backdrop of famous cultural landmarks. Recurring motifs in the novels include hidden codes, ancient societies, and philosophical questions about faith, knowledge, and mortality. Langdon’s expertise in the fictional field of symbology and his wide-ranging knowledge of other fields give him a unique perspective that is supported by a group of recurring characters that appear across the novels.


In the first book, Angels and Demons (2000), Langdon’s code-breaking skills enables him to prevent an anti-religious group called the Illuminati from destroying Vatican City during the election of a new pope. Brown found global commercial success with The DaVinci Code (2002), in which Langdon is accused of murdering the curator of the Louvre and must prove his innocence. The Lost Symbol (2009) introduces Langdon’s love interest Katherine Solomon, whose brother is kidnapped in Washington, DC, drawing Langdon and Solomon into the secrets of the Freemasons. In Inferno (2013), Langdon wakes up in a hospital in Florence, Italy, with no memory of the past four days, and must use clues from Dante’s text to escape a team of assassins. Origin (2017) follows Langdon to Spain as the sudden death of a former student draws him into a fierce debate about science and religion.


Like the previous novels in the series, The Secret of Secrets sees Langdon drawn into an international conspiracy, which requires his unique set of skills to unravel. Recurring characters in this novel include Langdon’s editor Jonas Faukman and love interest Katherine Solomon.

Historical Context: Parapsychology in the Military

In The Secret of Secrets, Robert Langdon uncovers a fictional military project called Threshold, which aims to weaponize the human mind by developing an army of psychic superspies. Although this project is fictional, the novel presents Threshold as an extension of the real-life Stargate Project, which was established by the US Army in Fort Meade, Maryland, in 1977 and terminated in 1995. Although it continues to be hotly debated, the real research conducted as a part of the Stargate project informs much of the fictional technology described in The Secret of Secrets.


The primary focus of the Stargate project was remote viewing, a term coined by physicists Harold Puthoff and Russell Targ to describe the ability to visualize distant or hidden targets. Puthoff and Targ’s research began at the Stanford Research Institute in Palo Alto, California, in the 1970s, funded initially by the CIA and the Defense Intelligence Agency, a branch of the Department of Defense. Puthoff and Targ worked with a number of self-proclaimed psychics to prove the viability of remote viewing as a surveillance technique for the Army, which took over the project in 1979. Many involved with the project claimed that it was successful, but that the popular stigma of parapsychic research meant that Army leadership was unwilling to publicly defend the research. When project was closed in 1995, a review of the program conducted by the CIA concluded that although the researchers had observed a statistically significant effect in the laboratory, they had not proven remote viewing was possible. The Secret of Secrets extends this story, providing a version of what the development of the project might look like in the present day.

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