Robert Langdon is a 5-book series with 5 primary works first released in 3 with contributions by Dan Brown and Dan Brown.
1980 • 1,496 Readers • 736 pages • 3.6
1977 • 1,866 Readers • 489 pages • 3.5
2009 • 692 Readers • 509 pages • 3.4
2013 • 641 Readers • 448 pages • 3.6