Arash convinces the Girl to leave Bad City with him.
The film takes place in an oil-producing part of Iran called Bad City. The city is full of sad and lonely people, with a culvert full of murdered and dead bodies lying in plain view. Arash (Arash Marandi) is a hard-working gardener who saved for seven years to buy a fancy new car. When he returns home after finding his family's runaway cat, he finds the local drug dealer Saeed (Dominic Rains) giving Arash's father Hossein (Marshall Manesh) some heroin. Once Hossein passes out, Saeed tells Arash that he must be paid and takes the keys to Arash's car. Arash is furious, but lacks the backbone to confront Saeed.
Saeed visits the local prostitute, Atti (Mozhan Marnò). While being serviced in his car, he notices a Girl (Sheila Vand) in a black, full-body chador. Seeing the Girl watching upsets him and he kicks Atti out of his car without payment. Later, he notices the Girl following him on the streets and decides to invite her to his place. Once there, he snorts cocaine and begins hitting on the Girl, sticking his finger in her mouth. The girl sprouts fangs, bites off his finger, and sticks Saeed's severed finger in his mouth. She then drains his blood and takes his jewelry.
As she leaves Saeed's apartment, she sees Arash waiting outside. Earlier, he stole some earrings from one of his client's beautiful but stuck-up daughters in order to pay Saeed and take back his car. Arash goes up to the apartment and discovers Saeed dead. He finds Saeed's cash and drug stash and steals it after dumping Saeed's body into the culvert. He also takes back his car.
Arash dresses up as Dracula and goes to a costume party where he begins selling Saeed's drugs. He finds his client's daughter there and she convinces him to take some drugs. They dance with each other and he attempts to kiss the daughter, but she is repulsed by his advances. Rejected and humiliated, Arash walks home in a drug-induced stupor. He gets lost on the way home. The Girl passes by Arash and is shocked to find a boy dressed as a vampire stumbling around at night. After some conversation, during which Arash hugs the girl because her skin feels cold, she invites him back to her apartment. She considers drinking his blood, but instead, the two embrace and listen to music. Arash wakes up at home the next morning.
Arash leaves notes at the Girl's apartment to meet him. They meet and he gives her the earrings he stole from his client's daughter. The Girl is clearly touched by the gesture, but ultimately rejects Arash, saying she is a bad person. Later, the Girl befriends Atti and realizes that Atti has dreams of fleeing Bad City to become a dancer. The Girl commiserates with Atti's loneliness and inability to move on in life. Meanwhile, upset that the Girl has rejected him, Arash is enraged when he finds that Hossein has trashed their house while suffering withdrawal. Arash throws Hossein out of the house and has Hossein take the cat with him. That morning, the Girl dreams of Arash.
Hossein buys some heroin and goes to Atti's place. Hossein insists Atti use the heroin with him. When she declines, he forcefully injects her. The Girl gets a vision of the assault and bursts in to Atti's apartment where she kills Hossein and drinks his blood. Atti is terrified and tells the Girl to take the cat and leave (and it is implied Atti will give up her life of prostitution and leave Bad City). Arash is devastated when he is informed of his father's death. Again, the Girl dreams of Arash.
Depressed, Arash goes to the Girl's apartment and asks her to run away with him. She complies and begins packing her belongings. While waiting for her, Arash sees his old cat in her apartment, as well as some of the jewelry she stole from Saeed. He realizes that the Girl killed both Saeed and his father. They begin to drive out of town when Arash pulls over, leaps out of the car, and starts pacing. The Girl stares wide-eyed, wondering what Arash will do. After some time, Arash gets back in the car, restarts it and he and the Girl look longingly at each other while listening to music. The implication is that he will accept the Girl despite her murderous nature and they will leave Bad City together.
Thanks Evan B!