The Black Vampire

Amalia, a glamorous nightclub singer, spots through a small barred window as a man dumps a small body into a storm drain in the alley behind the nightclub. The police later nickname the killer the vampire for his signature method. This glimpse links Amalia to the case and signals the danger ahead.

The killer dumps the body into the storm drain in the alley behind the nightclub. This act reinforces the serial nature of the killings and the killer's anonymity. Police will later refer to him as the vampire.

Government Prosecutor Dr. Bernard questions Amalia about what she witnessed. She denies having seen anything, fearing exposure of her nightclub job and the possible loss of custody for her daughter. The interrogation shows the tension between cooperating with the investigation and protecting her personal life.

A merchant seaman is arrested as the first suspect after being seen hiding in the crime scene. He is described as merely an adulterer having an affair with a married woman. The arrest opens the investigation to eventually rule him out.

Dr. Bernard quickly realizes the merchant seaman is not the killer, showing that the investigation still lacks the true culprit. This realization keeps the case unresolved and focused on the mysterious vampire.

The shy language teacher, Professor Ulber, disables the elevator in a girl's apartment building and catches her on the stairs, then kills her. This marks him as the killer and reveals his vampire persona. His method foreshadows the danger to other children.

The police stake out a little girl on a sidewalk, watching from a car in an attempt to trap the killer. The Professor, tempted by the bait, narrowly evades the trap. The sequence heightens the suspense around his next move.

Coincidentally, Ulber is an admirer of Cora, Amalia's co worker, whom he visits at the nightclub to stare at her. Cora tolerates him, occasionally ridiculing him, which sharpens his deviant fixation on children. This tension hints at a dangerous obsession.

Dr Bernard, driven by sexual frustration, questions Amalia again and cannot resist kissing her, though she rebuffs him. The moment adds tension between their professional and personal boundaries. This interaction complicates Amalia's relationship with the prosecutor.

Amalia tells Dr Bernard that she did see the vampire through her window and explains why she chose not to get involved. Her confession deepens the police interest while underscoring her fear of involvement. The truth remains dangerous for her and her family.

The police suspect Gastón, the nightclub owner, of narcotics trafficking and stage a raid on his club. He is shot and killed, and the club is closed. The raid removes another potential suspect from the scene while intensifying the investigation.

Amalia brings her daughter home from school and leaves her with Cora while she runs an errand. This places the child in a vulnerable position as the danger from Ulber looms. The arrangement shows Amalia juggling motherhood and danger.

Ulber visits Cora and, unaware of his true identity, gets permission to take Amalia's daughter for a walk. He takes her on rides at an amusement park, creating suspense that he may kill her. The scene heightens the terror of Ulber's predatory behavior.

A Norwegian beggar recognizes the tune Ulber whistles and sounds the alarm. Beggars and the police mobilize, chasing Ulber through the city and finally rescuing Amalia's daughter. The chase culminates in Ulber's capture.

Ulber is captured, tried, and sentenced to death by hanging. The film closes with the killer facing his doom for the murder of children. The story resolves with his punishment.