In 1815, Edmond Dantès, second mate of a French merchant vessel, and his friend Fernand Mondego, a representative of the shipping company, seek medical help on Elba for their ailing captain. Napoleon Bonaparte is in exile on the island. Having kept his guardians from killing the pair, Bonaparte privately requests that Edmond deliver a letter to the mainland in exchange for his physician’s services. Edmond is sworn to secrecy, but the exchange is witnessed by Fernand.
In Marseille, the company owner Morrell commends Edmond for his bravery, promoting him to captain over first mate Danglars, who had given Edmond explicit orders not to land at Elba. Edmond thereafter states his intention to marry his girlfriend, Mercédès, whom Fernand lusts after.
Envious of Edmond’s good fortune, Fernand and Danglars inform on Edmond regarding Bonaparte’s letter, which reveals information that could be used to aid Bonaparte’s escape from Elba. Villefort, the city’s magistrate, has Edmond arrested, but initially prepares to exonerate him until he learns the letter is addressed to Villefort’s father, Monsieur Clarion, a Bonapartist. He burns the letter and orders Edmond imprisoned in the Château d’If. Edmond escapes from Villefort and turns to Fernand for help, but Fernand instead turns him over to the pursuing gendarmes. Edmond is consigned to the island prison and its sadistic warden, Armand Dorleac. In exchange for persuading Mercédès that Edmond has been executed for treason and that she should take comfort in Fernand, Villefort has Fernand assassinate his father.
Six years later, Edmond is startled in his cell by an eruption in the ground revealing another prisoner. Abbé Faria, who has been imprisoned for 11 years after refusing to tell Bonaparte the whereabouts of the treasure of Spada, has dug an escape tunnel. However, upon seeing that he is in Edmond’s cell, he realizes he dug in the wrong direction. In exchange for Edmond’s help digging a new tunnel, Faria educates him in numerous fields of scholarship and swordsmanship over the next seven years. Faria is seriously injured in a tunnel cave-in, but before dying he gives Edmond a map to the treasure and implores him to use it only for good. Edmond escapes the prison by switching himself for Faria’s body in the body bag, and is thrown into the sea, pulling Dorleac along with him, whom he drowns.
Wading ashore, Edmond encounters a band of pirates preparing to execute one of their own, Jacopo. Their leader, Luigi Vampa, decides justice and entertainment would be better served by pitting Edmond and Jacopo in a knife fight. Edmond wins but spares Jacopo, who swears himself to Edmond for life. They both work with the pirates until they arrive in Marseille.
Edmond learns from Morrell, who does not recognize him, that Fernand and Danglars were complicit in his betrayal, and that Fernand and Mercédès wed shortly after Edmond was imprisoned. With Faria’s map, he and Jacopo locate the treasure of Spada on the island of Montecristo. Using his newfound wealth and advanced education, Edmond establishes himself in Parisian society as “The Count of Monte Cristo”, and swears vengeance on those who conspired against him.
Edmond ingratiates himself to the Mondegos by staging the kidnap and rescue of their son, Albert. He lures Fernand, Villefort, and Danglars into a trap by letting slip the notion that he has located the treasure of Spada, and is shipping it through Marseille. His plans result in Danglars being caught red-handed in the act of theft, and Villefort being tricked into revealing his role in his father’s death; both are arrested. Fernand is brought to financial ruin as Edmond has his gambling debts called in. Even though his appearance has changed dramatically, Edmond is recognized by Mercédès. Eventually, she softens him, and they rekindle their relationship. As Fernand prepares to flee, Mercédès reveals the only reason she married him was that she was pregnant with Albert, who is actually Edmond’s son.
Edmond ambushes Fernand in the ruins of his family’s country estate, having led him to believe that the treasure of Spada would be waiting for him. Albert intervenes when Edmond attempts to kill Fernand, but Mercédès tells him of his true parentage. Fernand attempts to flee, but changes his mind upon realizing that Edmond has everything and he has nothing, and challenges Edmond to a fight to the death; Edmond prevails. During the encounter, Mercédès is shot in the shoulder, but the wound is not fatal.
Edmond purchases Château d’If, intending to raze it, but instead leaves it standing as he swears to Faria to use his vast resources for good.