Plot
A documentary crew follows four vampire housemates—Viago, Vladislav, Deacon, and Petyr—who share a flat in the Wellington suburb of Te Aro. All of the vampires possess supernatural powers, including levitation and the ability to transform into animals. Viago is a 17th-century dandy who originally traveled to New Zealand in the 1940s in search of Katherine, the love of his life; Vladislav is a 12th-century former tyrant known as "Vladislav the Poker", who is haunted by memories of his nemesis "the Beast"; and Deacon is a 19th-century former peddler and the "young rebel" of the group who was turned into a vampire by Petyr—a reclusive, ancient vampire who behaves like a feral animal and resembles Count Orlok.
Each night, Viago, Vladislav, and Deacon take the bus into town and prowl the streets of Wellington to feed. Deacon's human familiar, Jackie, runs errands for the vampires and cleans up the gore left behind by their feeding. A married mother, Jackie hopes to attain immortality, but is frustrated that Deacon will not turn her into a vampire as promised. Deacon requests that Jackie bring virgins to the flat so that the vampires can feed on them. She lures a woman who insulted her in primary school and her ex-boyfriend Nick to the flat. Though neither are actually virgins, the woman is killed, and Nick is chased throughout the flat and manages to get outside, only to be caught by Petyr, who turns him into a vampire.
Two months later, the vampires accept Nick into their group and bond with his human friend Stu, a computer analyst who introduces them to modern technology. Viago uses the Internet to find Katherine, who is now a 96-year-old widow living in a rest home in Wellington, and also briefly reconnects with his old servant Philip.
Despite being able to get his new friends into popular bars and clubs, Nick struggles to adapt to life as a vampire. Nick is also held in contempt by Deacon, who resents Nick's newfound popularity and the careless revealing of his vampirism to strangers he meets. One of these strangers, a vampire hunter, breaks into the flat basement during the day and kills Petyr by exposing him to sunlight.
The vampires are furious when they discover Nick has indirectly caused Petyr's death, and Deacon tries to kill Nick before being interrupted by a police welfare check, but Viago hypnotises them into not noticing anything out of the ordinary. Once the police leave, Nick is banished from the flat by the remaining vampires, though Stu is permitted to come as he pleases.
Several months later, the vampires receive an invitation to the annual Unholy Masquerade, hosted for the local undead population of vampires, zombies, and witches. Vladislav refuses to attend after learning that "the Beast" will be the guest of honour. When Viago and Deacon arrive at the ball, they find in attendance Nick, Stu, and Jackie, the latter of whom has been turned into a vampire by Nick. "The Beast" is revealed to be Vladislav's ex-girlfriend Pauline, and when Stu and the camera crew are discovered to be living humans, the party guests threaten to kill and feed on them. Vladislav arrives and fights with Pauline's new boyfriend Julian. Stu impales Julian on a flagpole, and the vampires and camera crew escape the ball with him, only to encounter a rival pack of werewolves who transform under the full moon. One of the cameramen is violently murdered, and Stu is mauled and torn apart. Believing Stu to be dead, the vampires run away and grieve for him.
After an indeterminate amount of time, Nick returns to the flat with Stu, who reveals he has survived the attack and was transformed into a werewolf. With Stu's urging, the pack visits the vampires along with Stu, and Nick's banishment is rescinded as well. Though momentarily apprehensive, Deacon invites the werewolf pack inside. Viago also reconnects and rekindles his romance with Katherine, whom he turns into a vampire. Scenes during the credits reveal that Vladislav has gotten back together with Pauline, repeating his cycle of self-inflicted torture over his relationship with her, and Jackie's husband is now serving as her familiar. A post-credits scene shows Deacon attempting to hypnotise the audience to forget the events of the film.