Your Vice Is a Locked Room and Only I Have the Key

• The screenplay loosely adapts Edgar Allan Poe's 1843 short story 'The Black Cat' — keeping Poe's motifs of guilt, alcoholism, and a walled-up corpse, but reworking the confessional first-person tale into a giallo whodunit with a house full of suspects.
• The film's title is lifted from a line spoken in director Sergio Martino's earlier giallo 'The Strange Vice of Mrs. Wardh' (1971) — part of an informal run of Edwige Fenech-led gialli Martino made back to back in the early '70s.
• Bruno Nicolai composed the score, built around a mournful, harpsichord-led main theme that recurs through the film's murder sequences.
• The crumbling Rouvigny villa was actually shot on location at Villa Lugli in Bresseo di Teolo, in Italy's Veneto region — not, as sometimes assumed, in the Roman countryside.
• It's circulated under several alternate titles over the years, including 'Gently Before She Dies,' 'Eye of the Black Cat,' and 'Excite Me,' and was later packaged alongside Lucio Fulci's 'The Black Cat' (1981) in Arrow Video's 'Edgar Allan Poe's Black Cats' Blu-ray box set.

The entire narrative functions as Oliviero's drunken hallucination; the murders never occurred, and the 'killer' is merely a projection of his repressed desire to destroy his own lineage and escape his impotence.

Irina is the true architect of the carnage, manipulating Oliviero's blackouts to eliminate rivals and secure her inheritance, using the town's perception of him as a monster to cover her tracks.

The cat serves not just as a Poe homage but as a supernatural vessel for the dead mother's vengeance, physically guiding the killer's hand to punish Oliviero for his Oedipal failures.

Oliviero, a washed-up alcoholic writer drowning in wine and self-loathing, terrorizes his wife Irina while chasing other women behind her back. When a string of brutal murders rips through the household and the local vice trade, suspicion lands squarely on the blackout-drunk husband. But as bodies pile up and Oliviero's niece Floriana blows into town to stir the pot, the true killer is closer to home than anyone in the crumbling Rouvigny villa wants to admit. Martino twists the giallo screw until the screen bleeds, proving that in this house, the only thing more toxic than the wine is the bloodline.