The Secret of Secrets: Robert Langdon Book 6

In The Secret of Secrets, acclaimed author Dan Brown brings back Harvard symbologist Robert Langdon in what is described as his first novel in over eight years. The story begins when Langdon accompanies celebrated academic Katherine Solomon to Prague, where she has been invited to give a lecture. Almost immediately, Katherine disappears without a trace from their hotel room, and Langdon finds himself in a foreign city, thrown far out of his comfort zone, fighting against unseen forces to find the woman he cares for. 
Prague serves here not only as a backdrop but as a character itself: a city steeped in two thousand years of history, where castles loom, churches tower, and beneath the surface lie labyrinthine underground passages and graveyards layered deep. Langdon quickly realises he is in a shadow city hiding in plain sight, where ancient conspiracies and forbidden knowledge have echoed through time. 
As Langdon navigates through the cryptic ruins and coded symbols of this mysterious city, the stakes rise far beyond a rescue mission: he fights for the future of humanity itself. The novel weaves historical myth, art, architecture and symbology into a high-octane thriller where every clue could mean life or death. 
For fans of the Langdon series, this sixth instalment reconnects with the signature style of Brown’s earlier works — gripping pace, global scale, intellectual puzzles, and the moral question of how knowledge shapes the world. With a page-count of 688 pages and a UK publication date of 9 September 2025, this hardback edition offers a major event in modern thriller literature. 
Whether you are a long-time follower of Robert Langdon’s adventures or a new reader drawn by the promise of mystery and discovery, The Secret of Secrets offers a richly layered experience combining historical intrigue, architectural wonders, shadowy conspiracies and the timeless battle between hidden knowledge and power.