Professor Robert Langdon arrives at the Guggenheim Museum Bilbao to attend the unveiling of a discovery that "will change the face of science forever". The evening's host is his friend and former student, Edmond Kirsch, whose audacious predictions have made him a controversial figure around the world. But Langdon and several hundred other guests are left reeling when the evening is blown apart before Kirsch's precious discovery can be revealed. With his life under threat, Langdon and the museum's director, Ambra Vidal, flee to Barcelona on a perilous quest to locate a cryptic password that will unlock Kirsch's secret.