Angels & Demons (2000) is a mystery novel by Dan Brown who is well known for literary techniques which are well displayed in Angels & Demons, such as mysterious investigations into conspiracy theories and explorations in corrupt religious histories. This book is the first to feature Brown's main character, Robert Langdon, who is also the main character for three subsequent books by Brown: The Da Vinci Code, The Lost Symbol, and Inferno.
In 2003, The Da Vinci Code gained public acclaim in the media and among American readers, which may have reinforced the public reception of Angels & Demons. Brown has often been criticized for his employment of historical inaccuracies and his position against the Christian/Catholic churches, but he maintains that the Langdon series is not anti-Christian. Nevertheless, the books encourage a critical view on history and faith, and perhaps even a healthy skepticism.
Angels & Demons is a book that developes thrilling scenes from epiphanies about the interconnectedness of seemingly innocuous riddles. It acheives this by way of codes, symbols, abstraction and a persuasive narrative that leads the reader to feel their own mind challenged to reckon all of the data. Secret societies, obscure codes, impossible riddles, and corruption in Angels & Demons all combine into the foundation novel for Brown's Langdon series.
The story is epitomized as a power struggle between two old enemies: The Vatican, and the Illuminati. At the beginning of the story, an Illuminati conspirator steals a canister containing anti matter (or dark matter) and places it in the Acropolis (crypt) beneath the Basilica San Pietro (St Peter's Basilica). Not only is it a power struggle, but an allusion to the millenia-old debate between science and religion.