It is a worldwide bestseller with 36 million copies in print (as of August 2005) and has been translated into 44 languages. Combining the detective, thriller and conspiracy theory genres, the novel has helped generate popular interest in certain theories concerning the Holy Grail legend and the role of Mary Magdalene in the history of Christianity — theories that Christians typically consider heretical and that have been criticized as historically inaccurate. The book is part two of a trilogy that started with Brown's 2000 novel Angels and Demons, which introduced the character Robert Langdon. In November 2004, Random House published a "Special Illustrated Edition", with 160 illustrations interspersed with the text.

The book claims that the Catholic Church has been involved in a conspiracy to cover up the true story of Jesus. This implies that the Vatican consciously knows it is living a lie, but does so to keep itself in power. Fans have lauded the book as creative, action-packed and thought-provoking, while critics have attacked it as inaccurate and poorly written, and decry its controversial stance on the role of the Christian Church.

Description

The book concerns the attempts of Robert Langdon, Professor of Religious Symbology at Harvard University, to solve the murder of renowned curator Jacques Saunière (see Bérenger Saunière) of the Louvre Museum in Paris. The title of the novel refers, among other things, to the fact that Saunière's body is found inside the Louvre naked and posed like Leonardo da Vinci's famous drawing, the Vitruvian Man, with a cryptic message written beside his body and a Pentagram drawn on his stomach in his own blood. The interpretation of hidden messages inside Leonardo's famous works, including the Mona Lisa and The Last Supper, figure prominently in the solution to the mystery.

The main conflict in the novel revolves around the solution to two mysteries:

What secret was Saunière protecting that led to his murder?
Who is the mastermind behind his murder?

The novel has several concurrent storylines that follow different characters. Eventually all the storylines are brought together and resolved at the end of the book.

The unraveling of the mystery requires the solution to a series of brain-teasers, including anagrams and number puzzles. The solution itself is found to be intimately connected with the possible location of the Holy Grail and to a mysterious society called the Priory of Sion, as well as to the Knights Templar. The Catholic organization Opus Dei also figures prominently in the plot.

The novel is the second book by Brown in which Robert Langdon is the main character. The previous book, Angels and Demons, took place in Rome and concerned the Illuminati.

Characters

These are the principal characters that drive the plot of the story. It seems to be Dan Brown's style that many have names that are puns, anagrams or hidden clues:

Robert Langdon – A well-respected professor of Religious Symbology at Harvard University. At the beginning of the story, he is in Paris to give a lecture on his work. Having made an appointment to meet Jacques Saunière, the curator of the Louvre, he is startled to find the French police at his hotel room door. They inform him that Saunière has been murdered and they would like his immediate assistance at the Louvre to help them solve the crime. Unbeknownst to Langdon, he is in fact the prime suspect in the murder and has been summoned to the scene of the crime in order that the police may extract a confession from him.

Jacques Saunière – the curator of the Louvre, head of the secret Priory of Sion, and grandfather of Sophie Neveu. Before being murdered by Silas (an albino monk) in the museum, he reveals false information to Silas about the Priory's keystone, which contains information about the true location of the Holy Grail. After being shot in the stomach, he uses the last minutes of his life to arrange a series of clues for his estranged granddaughter Sophie to unravel the mystery of his death and preserve the secret kept by the Priory of Sion. Saunière's name may be based on Bérenger Saunière, a real person who was extensively mentioned in Holy Blood, Holy Grail.

Sophie Neveu – the granddaughter of Jacques Saunière. She is a French government cryptographer, who studied at the elite Royal Holloway, University of London Information Security Group. She was raised by her grandfather after her parents were killed in an automobile accident when she was a girl. Her grandfather used to call her "Princesse Sophie" and trained her to solve complicated word puzzles. As a girl, she accidentally discovered a strange key in her grandfather's room inscribed with the initials "P.S.". Later, as a college student, she made a surprise visit to her grandfather's house in Normandy and observed him participating in the Hieros Gamos, a sex ritual. The incident led to her estrangement with her grandfather for ten years until the night of his murder.

Bezu Fache – a captain in the Direction Centrale Police Judiciaire (DCPJ), the French criminal investigation police. Tough, canny, persistent, he is in charge of the investigation of Saunière's murder. From the message left by the dying curator, he is convinced the murderer is Robert Langdon, whom he summons to the Louvre in order to extract a confession. He is thwarted in his early attempt by Sophie Neveu, who knows Langdon to be innocent and surreptitiously notifies Langdon that he is in fact the prime suspect. He pursues Langdon doggedly throughout the book in the belief that letting him get away would be career suicide. "Bezu" is not a common French personal name, but "le Bezu" is the name of a castle in Rennes-le-Château with Cathar associations. When we first encounter Fache, he is compared to an ox; note that "Bezu" is an anagram (and the spoonerism) of zebu (zébu in French), a type of ox. Fâché is French for "angry", but "Fache" is also a reasonably common French surname, although it is pronounced differently from fâché.

Silas – an albino devotee of Opus Dei who practices severe corporal mortification. He was orphaned in Marseille as a young man, fell into a life of crime, and was imprisoned in Andorra in the Pyrenees until accidentally freed by an earthquake. He finds refuge with a young Spanish priest named Aringarosa, who gives him the name Silas and who eventually becomes the head of Opus Dei. Before the beginning of the events in the novel, Aringarosa puts him in contact with the Teacher and tells him that the mission he will be given is of utmost importance in saving the true Word of God. Under the orders of the Teacher, he murders Jacques Saunière and the other three leaders of the Priory of Sion in order to extract the location of the Priory's clef de voûte or "keystone". Discovering later that he has been duped with false information, he chases Langdon and Neveu in order to obtain the actual keystone. He does not know the true identity of the Teacher. He is reluctant to commit murder, knowing that it is a sin, and does so only because he is assured his actions will save the Catholic Church.
Bishop Manuel Aringarosa – the worldwide head of Opus Dei and the patron of the albino monk Silas. Five months before the start of the narrative, he is summoned by the Vatican to a meeting at an astronomical observatory in the Italian Alps and told, to his great surprise, that in six months the Pope will withdraw his support of Opus Dei. Since he believes that Opus Dei is the force keeping the Church from disintegrating into what he sees as the corruption of the modern era, he believes his faith demands that he take action to save Opus Dei. Shortly after the meeting with the Vatican officials, he is contacted by a shadowy figure calling himself "The Teacher", who has learned somehow of the secret meeting. The Teacher informs him that he can deliver an artifact to Aringarosa so valuable to the Church that it will give Opus Dei extreme leverage over the Vatican. The name "Aringarosa" seems to be the (approximate) literal Italian translation of "red herring" ("aringa rossa"; "aringa rosa" means, literally, "pink herring"), although this is not the expression used in Italian for "red herring" in its figurative sense.

The Teacher – a shadowy figure who drives the plot of the story. He has learned not only about the plight of Opus Dei, but also the identities of the four leaders of the Priory of Sion, who in turn know the location of the keystone. He contacts Aringarosa and agrees to supply him with a fantastic artifact that will give Opus Dei great power, namely documents that, if released, would destroy the Church. Aringarosa, acting out of self interest and piety, agrees to his offer in order to save both Opus Dei and the Church. The Teacher uses Silas, Aringarosa's protectee, to carry out his plans.

André Vernet – president of the Paris branch of the Depository Bank of Zurich. He is informed of Neveu and Langdon being wanted by the Direction Centrale Police Judiciaire by a security guard who recognized them from a television news report he had been watching before they had entered the bank. When Neveu and Langdon arrive Vernet met with them, his only plan in mind to get rid of them before the police arrive. They inform him that Jacques Saunière, a longtime account holder at the bank, has died and that Neveu now possesses the depository key, a Gold Key, to the account but did not know the account number. He is incapable of helping with the account information and leaves Neveu and Langdon alone to buy time from the police. Neveu and Langdon access the bank account with the key and figure out the account number after examining one of Saunière's clues he left behind, and retrieved a rosewood box from Saunière's safety deposit. When Vernet returns he is shocked to learn Neveu and Langdon figured out the account number. He is motivated to help them escape undected for two reasons: he doesn't want the bank to get bad publicity and Saunière was a close friend of his. Acting as a bank driver, he bluffs his way past the police in one of the bank's trucks with Langdon and Neveu concealed in the back of the truck. He later attempts to retrieve the rosewood box he believes they had stolen from Saunière after he hears on the radio Langdon is wanted for the murder of three others, the three other high ranking members of the Priory of Sion, the sènèchaux, and turn them in but he is thwarted by Langdon, who steals the truck and escapes with Neveu to the nearby château of his friend, Sir Leigh Teabing.

Sir Leigh Teabing – British Royal Historian, a Knight of the Realm, Grail scholar, and friend of Robert Langdon. Independently wealthy, he lives outside Paris in a château, where Langdon and Neveu take refuge after escaping from the Depository Bank of Zurich with the rosewood box containing the keystone. He reveals the "real" interpretation of the Grail to Neveu (see below). After they are discovered at his home simultaneously by Silas and the French police, the three of them flee with his chauffeur Rémy, flying to England in his private jet. They take Silas with them bound and gagged. After Neveu solves the combination lock of the keystone, he interprets the enclosed riddle as meaning they should go to the Temple Church in London to find the next hidden clue that will let them unlock the second combination lock of the keystone. Note that Sir Leigh's name is an anagram of the surnames of Michael Baigent and Richard Leigh — authors of Holy Blood, Holy Grail, a book which espouses very similar beliefs to Sir Leigh's. Teabing is revealed at the end of the story to be the Teacher.

Rémy Legaludec – chauffeur to Leigh Teabing. After flying with Teabing, Langdon, and Neveu to England, he drives them to the Temple Church in London. Unbeknownst to the others, he is in fact working for the Teacher. While they are inside the Temple Church, he rescues Silas, who was tied up by the other three. Armed with a pistol, he enters the church before the others can locate and solve the riddle supposedly hidden there. He takes Teabing hostage and demands the keystone from Langdon. When Langdon gives him the keystone, he and Silas flee in his car with Teabing as hostage. Rémy Martin is a famous brand of cognac, and cognac plays a role in Rémy's fate.

Lieutenant Collet – a lieutenant in the Direction Centrale Police Judiciaire (DCPJ). He is Fache's second-in-command in the case. Mostly a disappointment to Fache, Collet tries to redeem himself throughout the novel, but is also motivated by his own craving for glory and fear of risking his career by ignoring Fache's orders. By the end of the investigation Collet manages to share in the spotlight and to save Fache undue embarassment by crediting him for the arrest of the Teacher while also claiming that his misguided intent to arrest Neveu and Langdon was a ruse to draw out the real killer. By the end of the book Fache says of him, "A good man, that Collet."

The docent at Rosslyn Chapel – he is giving a guided tour of Rosslyn Chapel to Langdon and Neveu when he sees the rosewood box they are carrying and realizes that it seems to be an exact duplicate of a box owned by his grandmother, who is the head of the trust that oversees the chapel. He is revealed to be Sophie's brother.

Guardian of the Rosslyn Trust – she is, in fact, Marie Chauvel, the wife of Jacques Saunière and Sophie Neveu's grandmother. The docent is Sophie's brother. Believing that they had been targeted for assassination by the Church for knowing the powerful secret of the Priory of Sion, she and Saunière agreed that she and Sophie's brother should live secretly in Scotland. Only Sophie's parents were in the car at the time even though the whole family was supposed to be there. Saunière told the authorities that Sophie's grandmother and her brother were in the car. She tells Neveu and Langdon that although the Holy Grail and the secret documents were once buried in the vault of Rosslyn Chapel, they were removed to France by the Priory of Sion only several years ago. Reading the parchment inside the second keystone, she realizes where the Grail is now hidden, but refuses to tell Langdon, saying he will figure it out eventually on his own. According to her, the Priory of Sion never intended to reveal the secret of the Grail according to any set timetable. She believes that such a revelation is unnecessary anyway, since the true nature and spiritual power of the Grail is emerging into the world without the location of the actual artifact being revealed. She also informs Sophie Neveu of her true identity through her bloodline.