Netflix’s new Robert Langdon series takes Dan Brown’s The Secret of Secrets as its source material, the sixth novel starring the symbologist. The book was published on September 9, 2025, and production on the series began in Prague on September 4, 2026. Netflix still describes the project as an untitled series and has not announced a premiere date.
There is an important nuance: in August, Netflix described the project as an adaptation “based on” The Secret of Secrets; in September, it said the series is “set in the world” of the book. Both formulations confirm the reference work, but neither is enough to say the television version will follow every event in the novel literally.
Which book does the series adapt?
The short answer is The Secret of Secrets. In the latest Netflix Tudum report, the company says production has started in Prague and that the story follows Robert Langdon as he races to rescue a missing scientist and recover a manuscript whose discoveries could change humanity’s understanding of the mind.
The same report confirms Morgan Spector as Robert Langdon and Rebecca Hall as Katherine Solomon. Dan Brown and Carlton Cuse are co-creators, with Cuse also serving as showrunner and writer. Netflix frames the project as a blend of futuristic science, mystical lore, suspense, and historical investigation.
Where does The Secret of Secrets fall in the book order?
By publication order, The Secret of Secrets is the sixth Robert Langdon adventure. The official sequence can be checked on Dan Brown’s website and the Penguin Random House series page.
| Order | Book | Year |
|---|---|---|
| 1 | Angels & Demons | 2000 |
| 2 | The Da Vinci Code | 2003 |
| 3 | The Lost Symbol | 2009 |
| 4 | Inferno | 2013 |
| 5 | Origin | 2017 |
| 6 | The Secret of Secrets | 2025 |
That settles the main chronology question: the book behind the new series comes after Origin in Langdon’s bibliography. It is not a prequel to The Da Vinci Code, nor is it an adaptation of the third book simply because Katherine Solomon is also connected to The Lost Symbol.
Why can the screen adaptations make the order confusing?
The film and television versions were not released in the same sequence as the novels. Sony presents Angels & Demons as a film follow-up to The Da Vinci Code, even though Angels & Demons is Langdon’s first book and The Da Vinci Code is the second. The film franchise later adapted Inferno.
The Lost Symbol, meanwhile, received its own series, available on Peacock, with a different cast and a younger version of Langdon. So “what came first on screen” and “what comes first in the books” are separate questions.
What is Katherine Solomon’s role?
Katherine Solomon is central to the setup of The Secret of Secrets. The Penguin Random House synopsis describes her as a noetic scientist preparing to publish discoveries about human consciousness. She disappears along with her manuscript, triggering Langdon’s search through Prague.
In the Netflix series, Rebecca Hall plays Katherine. Carlton Cuse also told Tudum that Katherine’s relationship with Langdon reveals a new side of the character, presenting her as Langdon’s first serious love interest. That does not mean the series erases her earlier history: Katherine already belongs to the world of The Lost Symbol, and Penguin’s reading guide for that novel explicitly discusses her work in noetic science.
What Netflix has already confirmed
- the reference work is The Secret of Secrets, the sixth Robert Langdon novel;
- production began in Prague on September 4, 2026;
- Morgan Spector plays Robert Langdon and Rebecca Hall plays Katherine Solomon;
- Dan Brown and Carlton Cuse are co-creators, with Cuse serving as showrunner and writer;
- the premise involves a missing scientist and her manuscript, with an investigation blending science, mysticism, and history.
What has not been announced yet
As of Netflix’s September 4, 2026 announcement, the company had not announced a premiere date and still referred to the production as an “untitled” series. The official material consulted also does not spell out which events from the novel will be preserved, condensed, rearranged, or newly created for television.
The most accurate way to place the project today is therefore: the new series starts from The Secret of Secrets, Robert Langdon book 6, but the degree of fidelity to the novel has not been publicly defined. To follow the literary franchise, use the six-book publication order; to understand the adaptations, treat the films, Peacock series, and Netflix project as screen paths that do not automatically reproduce that sequence.
