A vampire named Louis tells his 200-year-long life story to reporter Daniel Molloy (who is only referred to as "the boy" in the novel).
In 1790, Louis was a young indigo plantation owner living south of New Orleans, Louisiana. Distraught with his brother's death, he seeks death in any way possible. Louis is approached by a vampire named Lestat, who desires Louis' company. Lestat turns Louis into a vampire (although initially Louis merely begs to be killed) and the two become immortal companions. Lestat spends some time feeding off the local plantation slaves while Louis, who finds it morally impossible for him to murder humans to survive, feeds from animals.
Louis and Lestat are forced to leave when Louis' slaves begin to fear the monsters with which they live and instigate an uprising. Louis sets his own plantation aflame; he and Lestat exterminate the plantation slaves to keep word from spreading about vampires living in Louisiana. Gradually, Louis bends under Lestat's influence and begins feeding from humans. He slowly comes to terms with his vampire nature but also becomes increasingly repulsed by what he perceives as Lestat's total lack of compassion for the humans he preys upon.
Escaping to New Orleans proper, Louis feeds off a plague-ridden young girl one night, no more than four or five years old, whom he finds next to the corpse of her mother. Louis begins to think of leaving Lestat and going his own way. Fearing that, Lestat then turns the girl into a vampire "daughter" for them, to give Louis a reason to stay. She is then given the name "Claudia".
Initially, Louis is horrified that Lestat has turned a child into a vampire, but instantly cares for Claudia tenderly and dotingly. Claudia takes to killing people easily, but over time begins to hate Lestat as she realizes she can never grow up; although her mind matures into that of an intelligent, assertive woman, her body remains that of a five-year-old girl. After 60 years of living together, Claudia hatches a plot to dispose of Lestat by poisoning him and cutting his throat. Claudia and Louis then dump his body into a nearby swamp. After realizing that they seem to now be the only vampires living in America, Claudia desires to travel to Europe with Louis and seek out "Old World" vampires.
As Louis and Claudia prepare to flee to Europe, Lestat appears, having survived and recovered from Claudia's attack, and attacks them in turn. Louis sets fire to their home and barely escapes with Claudia, leaving a furious Lestat to be consumed by the flames.
Arriving in Europe, Louis and Claudia seek out more of their kind. They travel throughout eastern Europe first and do indeed encounter vampires, but these vampires appear to be nothing more than animated corpses, mindless and unintelligible. It is only when they reach Paris that they encounter vampires like themselves - specifically, the 400-year-old vampire Armand and his coven, the Théâtre des Vampires. Inhabiting an ancient theater, Armand and his vampire coven disguise themselves as humans and feed on live, terrified humans in mock-plays before a live human audience (who think the killings are merely a very realistic performance). Claudia is repulsed by these vampires and what she considers to be their cheap theatrics. Santiago, a prominent figure among the vampire coven, suspects Claudia and Louis of killing their maker. One rule among the vampires is death to any vampire who kills their own kind.
Claudia demands that Louis turn a human Parisian dollmaker, Madeleine, into a vampire to serve as both a mother figure and a replacement for Louis (Claudia is convinced that Louis wants to be with Armand and will leave her). Louis at first refuses but, after realizing Claudia's plight, gives in and makes Madeleine into a vampire. Louis, Madeleine and Claudia live together for a brief time but all three are abducted one night by the Theatre vampires. Lestat has arrived - having survived the fire and attempted murder in New Orleans. His accusations against Louis and Claudia result in Louis being locked in a coffin to starve, while Claudia and Madeleine are locked in an open courtyard. Armand arrives and releases Louis from the coffin, but Madeleine and Claudia are burned to death by the rising sun. Louis finds the ashen remains of Claudia and Madeleine and is devastated. He later returns to the Theatre late the following night, burning it to the ground as the sun rises and killing all the vampires inside, and leaves with Armand.
Louis and Armand then travel across Europe together for several years, but Louis never fully recovers from Claudia's death. Tired of the Old World, Louis eventually returns to America and New Orleans in the early 20th century, living as a loner; he feeds off any humans that cross his path but lives in the shadows and never creates another companion for himself.
Telling the boy of one last (which is described in detail by Lestat in later books) encounter with Lestat in New Orleans, Louis ends his tale; after 200 years, he is weary of immortality as a vampire and all the pain and suffering to which he has had to bear witness. The boy, however, seeing only the great powers granted to a vampire, begs to be made into a vampire himself. Infuriated that his interviewer learned nothing from his story, Louis refuses, and attacks the boy, feeding off him and rendering him unconscious. He then vanishes without a trace.
Recovering from the attack, the boy notes the address of the house where Louis last saw Lestat in New Orleans, and then leaves to track down Lestat for himself.
Italiano
Il vampiro Louis de Pointe du Lac racconta la sua storia ad un giovane giornalista, Daniel Molloy: tutto inizia nel 1791, quando in seguito alla morte del fratello, Louis cade in preda alla depressione. Non vuole più vivere, ma non ha il coraggio di togliersi la vita, per cui Lestat de Lioncourt, un vampiro, gli dona la possibilità di vivere per sempre, nutrendosi di sangue e vittime umane.
Louis non riesce ad accettare completamente l’inevitabilità dell’omicidio e la sua anima è sempre dilaniata da questo tormento interiore che lui riconduce alla sua umanità latente. Quando sta per lasciare Lestat e proseguire la sua "vita" da solo, il suo creatore trasforma una bambina di 5 anni, Claudia, in un vampiro, e insieme la allevano. Il trio trascorre 60 anni insieme, quando infine Claudia decide di porre fine all’arroganza di Lestat e cerca di ucciderlo. Louis e Claudia, ora soli, partono per l’Europa alla ricerca di loro simili, e mentre viaggiano nei luoghi dove sono più diffuse le leggende sui vampiri, non trovano altro che cadaveri più o meno senzienti. Iniziano a temere di aver ucciso l’unico essere come loro, ma mentre si trovano a Parigi finalmente entrano in contatto con altri non-morti, i vampiri del Theâtre des Vampires, guidati da Armand.
Armand, un vampiro di 400 anni con l’aspetto di un adolescente, sembra un maestro molto più preparato di Lestat e Louis cade subito sotto il suo fascino, mentre Claudia se ne sente minacciata. Una sera, infatti, i vampiri fanno irruzione nell’appartamento dei due al Saint-Gabriel Hôtel e li catturano. Claudia sarà esposta alla luce del sole, mentre Louis, imprigionato in una bara murata sarà salvato da Armand.
Per vendicare Claudia, qualche giorno dopo Louis brucia il Teatro dei Vampiri insieme a tutti i suoi occupanti. Armand aveva precedentemente abbandonato il teatro, pertanto si salva dal rogo.
Tornato a New Orleans, Louis scopre che Lestat è ancora vivo, anche se in condizioni pietose: non riesce ad accettare i cambiamenti introdotti nella società dalla tecnologia; Louis, impietosito, se ne allontana.
Il giornalista è profondamente toccato dalla narrazione e non riesce a capire come possa Louis avere una concezione così pessimistica della vita eterna. A suo avviso, chiunque vorrebbe essere immortale, per cui supplica Louis di trasformarlo in vampiro, ma senza successo.