Volume I
The English ship's captain Robert Walton, in a series of letters to his sister Margaret Saville in England, describes the initial stages of his nautical journey to the North Pole (I: L1). While sailing north of Archangel in Russia, Walton's ship becomes trapped in arctic ice. From across the frozen sea, the sailors spot a gigantic figure on a dog-sled crossing the ice (I: L4: 3), and later see a haggard, wild-eyed man who is pursuing him, stranded with his dogsled on an ice floe. They take him on board.
This man, Victor Frankenstein, tells Walton that he is in pursuit of the figure they saw (I: L4: 12). While recuperating from exposure, he relates his history to Walton, who makes notes on the story and includes them in a letter to his sister.
Frankenstein describes his childhood in Geneva (I: 1): his father, Alphonse Frankenstein, was a wealthy descendant of Genevese nobility; his mother, Caroline, was the daughter of Beaufort, a friend of Alphonse who was reduced to poverty and died in his daughter's arms. Alphonse and Catherine are married, and Victor is their first child; two other sons, Ernest and William, follow. When Alphonse's sister dies, the Frankensteins adopt her young daughter Elizabeth, who is brought up as a member of the family. Victor and Elizabeth are the closest of friends, and with their friend Henry Clerval they live an idyllic childhood.
Whereas Elizabeth and Henry Clerval are fond of poetry and romance, Victor is fascinated by such mystical philosophers and alchemists as Cornelius Agrippa and Paracelsus, writers his father rejects as "sad trash" (I: 1: 15). But their pursuit of the elixir of eternal life continues to fascinate him, and a bolt of lightning striking a tree in the garden and reducing it to splinters fires Victor's imagination.
Elizabeth is taken ill, and although she survives, Caroline Frankenstein contracts the fever and dies from it. Her last wish is that Victor and Elizabeth may someday marry (I: 2: 2). After mourning his mother's death, Frankenstein goes up to the University of Ingolstadt without his friend Clerval. There he meets a professor of science, Krempe, who berates him for wasting his time on Agrippa and Paracelsus and suggests a more modern course of reading. Frankenstein is little impressed with his appearance or manner, though, and has little interest in the mundane work of modern scientists as compared with the fantastic dreams of the alchemists. Upon meeting another professor, however—Waldman—his attitude toward modern chemistry changes, and he begins to study with ardor, rapidly progressing in his knowledge.
Still filled with the grandiose dreams of the alchemists, Frankenstein devotes himself to study day and night, neglecting his family and friends. After two years of uninterrupted labor, he has discovered the secret that he has sought: the principle of life (I: 3). He imagines creating a new race of beings that will hail him as their creator. On a November night, he succeeds in bringing life to lifeless matter (I: 4). But when the eyes of his creature open, he is terrified by its appearance, and runs from it in horror. Fatigued from days of constant labor, he falls asleep and has a nightmare: he embraces Elizabeth, only to watch her turn into his dead mother, with worms crawling about her. He is suddenly awakened by the Creature standing over his bed; he then runs out of the room into the streets of Ingolstadt.
There he encounters Clerval (I: 4: 7), and the two return to Frankenstein's lodging, where Frankenstein is relieved to see the Creature has disappeared. But he falls into a fever, with only Clerval to nurse him back to health. After months of raving he comes to his senses, and he and Clerval set out on a walking tour of the area to calm his mind (I: 5: 16).
The two return to Ingolstadt to find a letter from Frankenstein's father announcing the strangling death of Victor's brother, William (I: 6: 2). They travel to Geneva, where a search for William's murderer is in progress. Outside the city, Victor spots his creation and is certain that the Creature is responsible for his brother's death, even though a beloved family servant, Justine Moritz, has been accused of the killing, having been found with the locket William wore the night of his death.
Frankenstein and Elizabeth are convinced of Justine's innocence, but at her trial (I: 7), Frankenstein, afraid of being thought mad, does not tell his story, and she is found guilty and executed. Her death and William's weigh heavily on Frankenstein, who blames himself as their true murderer.
Volume II
Frankenstein sets out to scale Mont Blanc (II: 2), and on a plain of ice, he is approached by the Creature, who tells his own story. He begins by describing the "original æra of [his] being," his first sensory impressions, and describes his earliest experiences.
The Creature's first encounter with humans comes as he enters a hut, causing its inhabitant to flee in terror (II: 3: 9)—the same terror he inspires in the residents of a village he enters, and after fleeing angry villagers he takes refuge in a "hovel" that allows him to see into an adjoining cottage. From there he silently watches the impoverished and despondent De Lacey family, consisting of the blind father, his son Felix, and his daughter Agatha; impressed with their "gentle manners," he secretly provides the family with firewood (II: 4: 7).
There he discovers the use of language and learns the rudiments of this "godlike science" (II: 4: 9) by listening to their conversations. His progress quickens with the arrival of the Arab Safie (II: 5: 4), whose language lessons he observes attentively. Volney's Ruins of Empire provides him with not only a grasp of the language but "a cursory knowledge of history" as well. As his knowledge of language and politics improves, he is able to make sense of "the history of [his] friends" (II:6:1), which he recounts to Frankenstein. He supplements his linguistic knowledge with the ability to read after discovering copies of Paradise Lost, Plutarch's Lives, and Goethe's Sorrows of Young Werther (II: 7: 3).
After observing the family for a year, he resolves to approach the blind De Lacey when he is alone (II: 7: 13). But before he is able to make his case, Felix rushes in and, believing his father to be threatened, beats the Creature, chasing him away. Once the De Laceys have fled their cottage, he burns it to the ground in a mad rage (II: 8: 13) and, discovering his origin in Frankenstein's journal, resolves to travel to Geneva to meet his creator. On the way, he tries to save a drowning girl on the way but is shot by her companion. He finally reaches Geneva and encounters a young boy, whom he resolves to make his friend, but the boy, who proves to be William Frankenstein, calls him a "Hideous monster!" and struggles to escape. The Creature kills him and frames Justine for the murder.
The narrative breaks off, and the Creature tells Frankenstein his demand: "You must create a female for me. . . . I demand it of you as a right which you must not refuse" (II: 9: 2). Frankenstein agrees only after the Creature promises to leave Europe forever.
Volume III
While Frankenstein tries to delay the fulfillment of his promise in Geneva, his father proposes that he follow his mother's dying wish by marrying Elizabeth (III: 1: 5). Although he looks forward to the wedding, Frankenstein is unwilling to marry until he has created the Creature's mate, he delays the event until he has finished a tour of Europe. In Strasburgh he meets Clerval, and the two travel across the Continent to London (III: 2: 1) and thence to Edinburgh. There Victor leaves Clerval and heads to the remote Orkney islands to fulfill his promise. But he is tortured with anxiety over the prospect of his two creations mating and propagating "a race of devils" (III: 3: 2), and he destroys the half-finished companion. Upon seeing this, the Creature, who has followed him across Europe, vows vengeance: "I shall be with you on your wedding-night."
Frankenstein sets out in the middle of the night in a small boat (III: 3: 24); after being carried away from the shore, he is relieved to reach land but is immediately accused of murder. He is carried before the magistrate, Mr. Kirwin (III: 4: 1), and charged with the murder of a man—whom he immediately recognizes as Clerval. He lapses into a nervous fever for two months; upon waking, he is cleared of the charges, and he travels with his father back toward Geneva. In Paris, he receives a letter from Elizabeth, which makes Frankenstein resolve to marry her at once, in spite of the Creature's threat (III: 5: 18).
Upon hearing Elizabeth's scream on their wedding night, Frankenstein realizes the true significance of this threat—he discovers Elizabeth's lifeless body (III: 6: 8), the news of which results in the death of Victor's father. Frankenstein sets out on a mission to destroy the Creature and embarks on "wanderings . . . which are to cease but with life" (III: 7: 3). He relates to Walton his travels across the frozen north, which take him at last to the ship where he is recovered. Here Frankenstein's narrative ends, and Walton continues his letters to his sister.
The sailors, still ice-bound, threaten mutiny and are calmed only when Frankenstein urges them on (III: Walton: 17), but two days later Walton agrees to return to England. Frankenstein, refusing to abandon his quest, resolves to continue northward, but his health fails him, and he dies.
Walton, hearing a noise in the dead man's room, enters it to find the Creature standing over his body (III: Walton: 35). After delivering an oration over the body, the creature vows to immolate his own body at the North Pole, and springs out the window onto the ice: "He was soon borne away by the waves, and lost in darkness and distance" (III: Walton: 48).