Stoker delves into the theme of good versus evil throughout the novel, withholding the triumph of good until the final pages. During this time, all characters are ensnared in the conflict, splitting into two factions: the forces of good, led by Dr. Abraham Van Helsing, and the forces of evil, commanded by Count Dracula.

The first and larger group, consisting of the good characters, rallies around Van Helsing. He is a doctor well-versed in medicine, philosophy, literature, and more. Arriving from Amsterdam at the behest of his former student, Dr. John Seward, Van Helsing comes to aid in diagnosing and treating Lucy Westenra. Older and more educated than the rest, he assumes the role of a father figure and leader. Unlike the others, he is knowledgeable about vampire folklore and methods to combat them.

Van Helsing is supported by a group of young men, many of whom have connections to Lucy. Dr. John Seward, who unsuccessfully courted Lucy, directs an insane asylum. Another unsuccessful suitor is Quincey Morris, a Texan distinguished by his physical bravery. The final suitor—Lucy receives three proposals in one day—is Arthur Holmwood, whom she accepts. Following his father's death during Lucy's illness, Arthur inherits his title and becomes Lord Godalming. These three men, who have shared past adventures, grow closer due to their love for Lucy. The group's last member is Jonathan Harker, a lawyer whose journal about his trip to Dracula's castle forms the novel's opening. After recovering, he marries Lucy's friend Mina. Harker's previous encounters with Dracula render him particularly valuable to the group.

The two young women in the group are introduced through their letters, which follow Harker's journal. Though associated with Van Helsing and his band, both women are drawn towards Dracula. Lucy, exceedingly beautiful but lacking strength of character, transforms into a vampire under Dracula's influence, shifting from sweetness to seductiveness. Her friend Mina, more securely protected by her marriage to Jonathan, survives Dracula's attack and becomes the group's secretary and inspiration. Her blood exchange with Dracula has beneficial outcomes, providing the group with insights into Dracula's actions and whereabouts. Dracula's death ultimately liberates her from his influence.

The characters aligned with evil are all connected to Dracula. At the novel's start, he has been a vampire for many centuries, possessing immense strength and power. He achieves his malevolent aims primarily through weak links: women, an insane man, and an unsuspecting, vulnerable foreigner. His "children," the vampires he has created, are all women, including the alluring female vampires residing with him at his castle. They are depicted as unnatural, preying on children and acting aggressively and seductively toward men. Lucy exhibits similar behavior after becoming a vampire.

Renfield, a patient at Seward's asylum, is Dracula's primary accomplice. Obsessed with the concept of the food chain, Renfield feeds flies to spiders and spiders to birds. This fixation makes him an ideal admirer of Dracula, who, by preying on humans, sits at the apex of the food chain. Initially, Renfield eagerly anticipates Dracula's arrival, growing more excited as the count approaches the asylum. However, he eventually regains his sanity and suffers a fatal injury while attempting to thwart Dracula.

In the novel, the evil characters are not only vanquished but also redeemed by the virtuous ones, highlighting Stoker's theme that good ultimately triumphs over evil. At first, Dracula appears invincible, but his vulnerabilities gradually become evident. He can be repelled by consecrated wafers (which, in the Roman Catholic Church, represent the body of Christ) and other religious symbols like the crucifix. Ultimately, he is destroyed with knives. Furthermore, characters who possess strong spiritual fortitude can withstand his attacks, underscoring Stoker's belief in an individual's ability to control both their soul and their life.