THE LITTLE GIRL WHO LIVES DOWN THE LANE

On Halloween night, in a seaside town, Rynn Jacobs celebrates her thirteenth birthday alone. She and her father, Lester Jacobs, a poet, have recently moved to the village from England. Frank Hallet, adult son of their landlady Cora Hallet, visits unexpectedly and, finding her alone, makes sexual advances toward Rynn.

The following day, Cora Hallet comes to the house, first obtrusively poking around the garden, then coming inside and aggressively probing Rynn with pointed questions about herself and her father. Rynn says he is in New York with his publisher and taunts the landlady about her son's intentions. The situation becomes more tense when Mrs. Hallet insists on retrieving jelly glasses she left in the cellar. Rynn makes it obvious she is unwilling to let her landlady go down into the cellar, and Mrs. Hallet finally leaves. She returns later and opens the cellar trapdoor over Rynn's objections. Upset by what she sees there, Mrs. Hallet attempts to flee, but in her haste she knocks down the support. The cellar door falls on her head, killing her.

Attempting to remove evidence of Mrs. Hallet's visit, Rynn goes outside to drive her car away but cannot start it. This attracts the attention of Mario, a teenager passing by. Mario is the nephew of Officer Miglioriti, a village policeman who previously had given Rynn a ride home from town. Mario drives the car back to town, and Rynn rewards him with a dinner she prepares at her house.

Later, Officer Miglioriti stops by and tells them Frank Hallet has reported his mother missing. The officer asks to see Rynn's father, but Mario covers for Rynn by saying her father has gone to bed. Later that night, Frank Hallet makes a surprise visit. Suspicious, and looking for answers about the whereabouts of his mother and Rynn's father, Frank tries to scare Rynn into talking, cruelly killing her pet hamster. Mario chases Frank away.

Rynn now trusts Mario and confesses her actual situation. Rynn's terminally ill father and abusive mother divorced long ago. To protect Rynn from being returned to her mother's custody after his death, her father moved them to America and made arrangements to allow Rynn to live alone, then committed suicide in the ocean when the tides would carry his body out to sea. Her father also left Rynn a jar of potassium cyanide, telling her that it was a sedative to calm her mother if she ever came for her. Rynn coolly recounts how she put the powder in her mother's tea and watched her die.

Trust between Rynn and Mario blossoms into romance. On a cold, rainy day, they bury the bodies behind Rynn's house, but Mario catches cold. Suspicious of Rynn's continued evasions regarding her father's absence, Officer Miglioriti returns to the house one night and demands to see her father. Mario disguises himself as an old man and introduces himself to Miglioriti as Rynn's father. After Miglioriti leaves, Rynn and Mario go upstairs, where they undress and get in bed together.

As winter sets in, Mario is hospitalized after his cold causes pneumonia. Rynn visits an unconscious Mario in the hospital making her feel lonely. That night, as Rynn is going to bed, she is shocked to find Frank emerging from the cellar. Frank thinks he knows what happened to Rynn's parents and his mother, and attempts to blackmail Rynn. He offers to protect Rynn's secrets in exchange for her sexual favours. Rynn, seemingly defeated and resigned to Frank's demands, agrees to have tea with him. Rynn puts some of the cyanide in her own cup and then takes the tea and almond cookies into the living room. Suspicious, Frank switches his cup with hers. Rynn watches intently as Frank succumbs to the poison.