In Paris, Jacques Saunière is pursued through the Louvre's Grand Gallery by albino monk Silas(Paul Bettany), demanding the Priory's clef de voûte or “keystone” Saunière confesses the keystone is kept in the sacristy of Church of Saint-Sulpice “beneath the Rose” before Silas shoots him. At the American University of Paris, Robert Langdon(Tom Hanks), a symbologist who is a guest lecturer on symbols and the sacred feminine, is summoned to the Louvre to view the crime scene. He discovers the dying Saunière has created an intricate display using black light ink and his own body and blood. Captain Bezu Fache(Jean Reno)asks him for his interpretation of the puzzling scene.
Silas calls a mysterious man known as “The Teacher”, revealing that he has killed all four protectors of the keystone and that all confirmed the same location. He dons a metal cilice on his thigh and proceeds to flagellate himself with a whip for the sins of murder Facilitated by Bishop Manuel Aringarosa(Alfred Molina), Silas then travels to Saint-Sulpice and is admitted by an elderly nun; left alone, he excavates beneath the floor of the church to find a stone saying only JOB 38:11, He confronts the nun, who quotes the passage: “Hitherto shalt thou come, but no further,” Realizing that he has been deceived, Silas is enraged and kills the nun.
Sophie Neveu(Audrey Tautou), a cryptologist with the French police, enters the Louvre as well and slips Langdon a message which leads him to the bathroom. There, Sophie meets him and tells him that he is being tracked, a GPS tracking dot has been(unknown by him)slipped into his jacket and that he is a primary suspect in the murder case because of a line of text found by the corpse(“P.S. find Robert Langdon”). Sophie however, believes that Saunière, who is revealed to be her grandfather, wanted to pass a hidden message on to her(Princesse Sophie, P.S., was the nickname he used for her), and that he had wanted to bring Langdon into the equation so that he could help her crack the code.
Buying some time by throwing the tracking device into the back of a truck, the pair begin exploring the Louvre, finding more anagram messages that Saunière had left behind. Many of these relate to Leonardo da Vinci's art, and the pair find a key with a Fleur-de-lis behind Madonna of the Rocks. Langdon deduces from this that Saunière was a member of the Priory of Sion, a secret society associated with the Knights Templar.
Pursued by the French police and cut off from the United States Embassy, the pair escape to the Bois de Boulogne where Langdon closely inspects the key. He notices an inscription on the side — an address. The address directs them to the Depository Bank of Zurich where the key is used for a safety deposit box.
In the bank, they find Saunière's deposit box and open it using the 10 digit Fibonacci numbers in order(1123581321). Inside the box, they find a rosewood container, which contains a cryptex: a cylindrical container with five alphabetical dials which must be arranged in the correct sequence to spell out a 5-letter code word, in order to open and access the papyrus message inside. Using force to open the cryptex would break a vial of vinegar inside, which would dissolve the papyrus and destroy the message.
Unfortunately, the police are called by a security guard and they are forced to leave. The bank manager, Andre Vernet(Jürgen Prochnow), assists them in escaping by taking them as passengers in an armoured van to escape the routine checks of the police. In the back of the truck Langdon and Neveu have a lengthy discussion about the cryptex and Neveu says that her grandfather often played games with her involving cryptexes. Langdon says that the cryptex might hold valuable information or another due about what they are trying to discover. Eventually, they come to a sudden stop and Vernet forces them at gunpoint to give him the cryptex. Langdon tricks Vernet and disarms him and he and Sophie escape with the cryptex in their hands.
Langdon suggests that they visit his friend, Leigh Teabing(Ian McKellen), for assistance to opening the cryptex. Leigh Teabing turns out to be an enthusiastic seeker of the Holy Grail, which he believes is not actually a cup but instead Mary Magdalene. Mary was pregnant at the time of Christ's crucifixion, and Teabing tells Sophie that the Priory of Sion was formed to protect the descendants of Jesus. Jacques Saunière was believed to be a part of this society and Teabing suspects that he was training Sophie to join it also. Silas, meanwhile, breaks into Teabing's mansion and attempts to steal the cryptex. Teabing uses his cane to knock Silas out and they escape again, taking the butler, Remy Jean, and Silas with them. The group escapes in Teabing's plane, following the next clue to London. Fache learns of their destination, and alerts the London Metropolitan Police to apprehend them at the airport. But Teabing manages to slip the party past the police with a trick of misdirection.
Teabing leads Langdon and Nsveu to the Temple Church in London, which is shown to be a red herring. Silas is freed by Remy Jean, who is revealed to be a follower of The Teacher as well. The two take Teabing hostage, and Silas, believing Remy to be The Teacher, holes up in an Opus Dei safehouse. Remy is killed by the mysterious man after deceiving Silas. Silas accidentally shoots Aringaros and is shot by the police. Aringarosa is taken to the hospital and apprehended by Fache.
Langdon is betrayed by Teabing, who is revealed to be the true Teacher. He escapes with the Cryptex, and attempts to find the next clue at Isaac Newton's tomb in Westminster Abbey, as Newton was another member of the Priory. Langdon and Neveau catch up with him, and chase him into the nearby chapter house. Teabing explained that he wanted to find Mary Magdalene's remains to prove he was correct about the Holy Grail and threatens to shoot Sophie if Langdon does not open the cryptex. Langdon throws the cryptex into the air, and Teabing fumbles and destroys it.
Distraught at not receiving the code, Teabing is arrested, but Langdon had cracked the code(“Apple”,a reference to Newton)and removed the clue from the cryptex before destroying it. Using the clue, they travel to Rosslyn Chapel in Scotland where Magdalene's remains had previously been hidden. The remains had since been moved, but they meet other members of the secret organization that protected her. Sophie is actually Magdalene's descendant and therefore is the current living descendant of Jesus Christ. They vow to keep her safe before going their separate ways. In Paris, Langdon accidentally cuts himself while shaving and the line of blood on the sink reminds him of the Rose Line. He follows the Rose Line and finds the location of the Holy Grail, buried under the pyramid in the Louvre. Langdon then kneels above Mary Magdalene's tomb as the Knights Templar did before him.
在巴黎的盧浮宮,白化病僧侶塞拉斯(保羅·貝坦尼飾)逼問雅克·索尼埃拱心石的下落,索尼埃供認(rèn)拱心石在圣蘇比教堂的圣器收藏室里且位于“玫瑰的下面”,隨后塞拉斯將其擊斃。巴黎美洲大學(xué)的符號學(xué)和神秘女性學(xué)客座講師、符號學(xué)專家羅伯特·蘭登(湯姆·漢克斯飾)被邀請到盧浮宮查看犯罪現(xiàn)場。蘭登發(fā)現(xiàn)索尼埃臨死前用黑光墨水、自己的軀體和血擺成了復(fù)雜的圖形。貝祖·法希警長(讓·雷諾飾)請他解釋這令人費(fèi)解的場景。
塞拉斯打給一個(gè)名為“老師”的神秘人物,告訴他已經(jīng)把四名拱心石守護(hù)者殺死,四人確認(rèn)的都是相同的地點(diǎn)。因?yàn)榉赶轮\殺的罪行,塞拉斯在大腿上綁上金屬粗布,用鞭子抽打自己。通過曼紐爾·阿林加洛沙主教(阿爾弗雷德·莫里納飾)的幫助,塞拉斯到達(dá)圣蘇比教堂,并得到年長修女的認(rèn)可,讓他獨(dú)自一人活動。他挖開教堂地板,找到一塊石頭,上面只寫著“《約伯記》38章11節(jié)”,他找到修女,修女引出原文:“你只可到這里,不可越過。”塞拉斯意識到自己受騙了,憤怒之下把修女殺害。
密碼學(xué)家索菲·奈芙(奧黛麗·塔圖飾)和法國警察一起來到盧浮宮,她塞給蘭登一張紙條讓他去洗手間,在那里,索菲告訴蘭登他被跟蹤了,他身上的夾克里被偷偷裝進(jìn)一個(gè)GPS定位跟蹤器(蘭登并不知情),因?yàn)榫桨l(fā)現(xiàn)的線索中有一句話“附言:找到羅伯特·蘭登”,他現(xiàn)在已被鎖定為頭號嫌疑犯。而索菲原來是索尼埃的孫女,她相信祖父想將一個(gè)秘密信息傳遞給她(“索菲公主”是祖父給她取的昵稱),索尼埃把蘭登牽扯進(jìn)來,是想讓他幫助索菲破解密碼。
他們花了一些時(shí)間把跟蹤器扔到一輛卡車后面,便開始在盧浮宮內(nèi)勘察,兩人發(fā)現(xiàn)了更多索尼埃用回文構(gòu)詞法留下的信息,多與李奧納多·達(dá)芬奇的作品有關(guān),他們還在油畫《巖間圣母》的后面找到帶有鳶尾花的鑰匙,據(jù)此,蘭登推測索尼埃是郇山隱修會——一個(gè)與圣殿騎士有關(guān)的秘密組織——的成員。
兩人遭到法國警方的追捕,與美國大使館切斷了聯(lián)系,逃到布洛浬森林,在那里蘭登仔細(xì)研究了鑰匙,他注意到在鑰匙的一面刻有一個(gè)地址,地址是在一間蘇黎世儲蓄銀行,鑰匙是用來開一個(gè)保險(xiǎn)盒的。
兩人在銀行找到索尼埃的保險(xiǎn)盒,用十位以斐波納契數(shù)列排序(1123581321)的數(shù)字打開了保險(xiǎn)盒。保險(xiǎn)盒內(nèi)是一個(gè)玫瑰木容器,里面有一個(gè)圓柱容器的密碼筒,上面是五個(gè)按字母排序的刻度盤,肯定是按照正確順序排列好的五個(gè)字符單詞的密碼,解開后才能取出里面記有重要信息的紙莎草紙。如果用暴力打開會打碎里面的小醋瓶,銷毀里面的紙莎草紙和信息,
不幸的是,銀行保安報(bào)警了,他們被迫離開這里,銀行經(jīng)理安德烈·弗耐特(尤爾根·普洛斯渃飾)協(xié)助他們,讓他們喬裝成乘客坐在裝甲小貨車后面躲開了警察的檢查。在貨車后面,蘭登和奈芙開始了關(guān)于密碼筒的長時(shí)間討論,奈芙說祖父以前經(jīng)常和她玩有關(guān)密碼筒的游戲,蘭登說密碼筒的里面應(yīng)該是有價(jià)值的信息或是他們尋找目標(biāo)的線索。結(jié)果,小貨車突然剎車,弗耐特用槍指著他們,逼他們交出密碼筒,蘭登欺騙了他,并把他的槍奪走,和索菲帶著密碼筒逃走了。
蘭登提議去投奔他的朋友雷·提彬(伊恩·麥克萊恩),幫助他們打開密碼筒。雷·提彬是個(gè)圣杯狂熱追隨者,他認(rèn)為圣杯不是個(gè)杯子,而是抹大拉的馬利亞。馬利亞在耶穌被釘十字架的時(shí)候懷孕了,提彬告訴索菲,郇山隱修會是為保護(hù)耶穌的后代而成立的。有人認(rèn)為索尼埃是郇山隱修會的一員,提彬懷疑他原是想訓(xùn)練索菲人會的。這時(shí)塞拉斯闖入提彬的住宅,試圖偷走密碼筒。提彬用手杖將塞拉斯敲暈了,隨后他們帶著男管家雷米·簡和塞拉斯坐著提彬的飛機(jī)再一次逃走,跟著下一條線索飛往倫敦。法希得知他們的目的地后,提醒他們倫敦警察廳正奉命在機(jī)場逮捕他們,提彬設(shè)法用錯(cuò)誤的指示躲過了警察。
提彬把蘭登和索菲帶到倫敦圣殿教堂,那是個(gè)與目的地不相干的地點(diǎn)。雷米·簡其實(shí)也是老師的跟隨者,他將塞拉斯松綁。兩人將提彬作為人質(zhì),塞拉斯以為雷米就是“老師”,藏在天主事工會避難所。雷米在欺騙塞拉斯后被神秘人物刺殺,塞拉斯意外射中阿林加洛沙主教,隨后被警方擊斃。阿林加洛沙主教被送往醫(yī)院后被法希逮捕。
真正的老師是提彬,他背叛了蘭登,帶著密碼筒逃往威斯敏斯特教堂的艾薩克·牛頓墓尋找下一條線索,因?yàn)榕nD也是郇山隱修會的成員。蘭登和奈芙趕上了提彬,跟蹤他到附近的牧師會禮堂。提彬說他想找到抹大拉的馬利亞的尸體,以證實(shí)他關(guān)于圣杯的猜測是正確的。提彬威脅蘭登,如果不把密碼筒解開,就把索菲擊斃。蘭登把密碼筒扔向天空,提彬沒有接到,密碼筒摔壞了。
因未能接到密碼筒而心煩意亂的提彬被捕,而蘭登其實(shí)早已解開密碼(“蘋果”,與牛頓相關(guān)),并且在損毀密碼筒之前將線索取出。通過線索,他們前往從前藏匿抹大拉的尸體的蘇格蘭的羅斯林教堂,遺體已被移走,他們遇到秘密組織的其他保護(hù)遺體的成員,他們稱索菲就是抹大拉的后代,也就是耶穌基督在世的后代。他們發(fā)誓在各奔東西前會保護(hù)索菲?;氐桨屠?,蘭登在刮胡子時(shí)不小心劃傷了自己,水池里的血跡讓他想起了玫瑰線,他沿著玫瑰線找到了圣杯所在地,埋藏在盧浮宮的金字塔下。蘭登在抹大拉的馬利亞墓上跪下,像從前的圣殿騎士一樣。