Your Vice Is a Locked Room and Only I Have the Key (1972)

An American writer living in Rome witnesses an attempted murder that is connected to an ongoing killing spree in the city and conducts his own investigation, despite he and his girlfriend being targeted by the killer.

An English pianist living in Rome witnesses the brutal murder of his psychic neighbor. With the help of a tenacious young reporter, he tries to discover the killer using very unconventional methods. The two are soon drawn into a shocking web of dementia and violence.

A young opera singer is stalked by a deranged fan bent on killing the people associated with her to claim her for himself.

Single father and former cop Tom Cutler has an unusual occupation: he cleans up death scenes. But when he's called in to sterilize a wealthy suburban residence after a brutal shooting, Cutler is shocked to learn he may have unknowingly erased crucial evidence, entangling himself in a dirty criminal cover-up.

Two veteran New York City detectives work to identify the possible connection between a recent murder and a case they believe they solved years ago; is there a serial killer on the loose, and did they perhaps put the wrong person behind bars?

A schoolgirl was murdered seven years ago, and the case was never solved; now, the murderer seems to be back.

After a car accident that caused the loss of her baby, Jane experiences an increasing amount of nightmares that shake her to her core. After seeking professional help, her haunting visions turn into an even more frightening reality, one full of black magic, blood orgies, and murder.

A private investigator helps a former flame solve the murder of her wealthy grandfather, who lived in a sprawling estate surrounded by his idiosyncratic family.

A series of random suicides in Rome, Italy are attributed to a heatwave, but a young pathologist named Simona—who is working on a thesis about murders disguised as suicides—suspects otherwise. When a young girl associated with Simona's playboy father ends up dead in another apparent suicide, Simona teams up with the girl's priest brother to prove she was murdered and track down the unknown serial killer.

A journalist finds himself on the trail of a murderer who's been targeting people around him, while the police are considering him a suspect in their investigation.