The Long Hair of Death

• Director Antonio Margheriti spent most of his career in Italian science fiction, Eurospy, and action pictures (Battle of the Worlds, Wild, Wild Planet); gothic horror like this one was a side lane he worked in occasionally, alongside the same year's Castle of Blood.
• The film was shot at Castello Massimo in Arsoli, with additional work at Cinecittà Studios in Rome — not at Bracciano, as sometimes claimed.
• Barbara Steele played a dual role: Helen Rochefort, the daughter murdered early in the story, and Mary, the mysterious woman who arrives at the castle years later claiming no connection to the family she's about to destroy.
• Released in Italy as 'I lunghi capelli della morte,' the film reached U.S. screens in 1965 through the Woolner Brothers, not American International Pictures.
• Margheriti released much of his international work, including this one, under the pseudonym Anthony M. Dawson.

The returning dead woman's long hair functions as a visual metaphor for trauma that refuses to be cut or contained, growing past death itself — suggesting the film is really about how violence against women persists across generations.

Helen's return from the grave as "Mary" can be read as psychological projection rather than literal resurrection — the Humboldt household's own guilt manifesting a vengeful double for the daughter they got away with murdering, rather than a straightforward ghost story.

The film's recurring fire imagery — the execution pyre at the start, the burning climax at the end — suggests a cyclical structure where violence begets violence, and the revenge that closes the film is less supernatural justice than the same wheel turning a second time.

Adele Karnstein burns at the stake for witchcraft that's really just cover — Count Franz Humboldt wants her and can't have her, so he has her killed, and she curses his bloodline as the flames take her. Her older daughter Helen confronts the count over it and is murdered for her trouble; her younger daughter Lisabeth gets absorbed into the Humboldt castle and married off to the count's weak-willed son, Kurt. Years later, lightning splits Helen's grave and a woman calling herself Mary — Barbara Steele playing both roles — turns up at the castle, the spitting image of the daughter the family murdered. What follows isn't a simple haunting: Mary works her way inside the household, gets close to Kurt, and turns the family's guilt and lust back on itself long before anyone realizes the "ghost" has been running a con the whole time. Margheriti closes it out the way it opened — fire, a body strapped down to burn, and a family finally paying for a crime nobody was ever punished for.