Robert Langdon, a professor of symbology at Harvard University, wakes up at midnight with a painful head injury, finding himself in the hospital. He cannot recall anything from the last thirty-six hours or the source of the terrifying object doctors discovered among his belongings.

Chaos ensues in Langdon's world, forcing him to flee through the streets of Florence with the help of a young woman named Sienna Brooks, who saved his life with her clever actions. He discovers he possesses a set of dangerous symbols crafted by a brilliant mind.

The events rapidly unfold across famous landmarks like the Palazzo Vecchio, as Langdon and Brooks uncover a network of ancient passageways, along with a frightening new scientific model that could either enhance life on Earth or destroy it.

Against this backdrop, Langdon battles a formidable opponent while grappling with a mystery that leads him into the realm of classical arts, secret passages, and futuristic sciences, all in pursuit of answers and discovering who deserves his trust before the great collapse.