A composer, Andrea Occhipinti, is given a chance to write music for an Italian horror film and takes up residence in a beautiful villa to focus on his work. However, the presence of female visitors and unsettling events—including a murder committed with a utility knife—disrupt his concentration. “A Blade in the Dark” (1983), directed by Mario Bava’s son, feels more like a standard slasher film than a giallo. It draws influence from movies such as “Psycho,” “Home for the Holidays,” and “Halloween,” along with an unnamed Brian De Palma picture. "Swimming Pool" clearly took cues from its cinematic environment two decades later, though it doesn't fit neatly into the slasher category itself. The movie was filmed entirely at the producer’s villa, with the exception of a single scene shot on a Rome street. Originally conceived as a four-part mini-series—with each segment culminating in a murder—the project was deemed too violent for television networks. It subsequently appeared as a 97-minute film, but the complete version, extended by an additional 11 minutes, eventually surfaced, and that’s what I experienced. Avoid the English dub; it's poorly done and unintentionally funny. If you understand English, watch the subtitled version instead. Some viewers find the pacing sluggish and the setting repetitive, but I found it acceptable for what it is, even though I guessed the identity of the killer roughly 20 minutes before the end. The actresses are adequate: Fabiola Toledo portrays Angela, Lara Lamberti plays Julia (also credited as Lara Naszinski), Valeria Cavalli appears as Katia and Anny Papa is Sandra. The film’s Italian title translates to “House of the Dark Stairway” or "House of Dark Stairs." Its total length is 1 hour, 48 minutes. GRADE: B

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