Underappreciated masterpiece by Argento is a textbook example of how to create terror and suspense. The story follows a basic giallo formula - a jazz pianist witnesses a murder and tries to track down the killer. Lots of twists and turns in the plot, with a superb ending. The slasher element is minimized, with only a few murders, although they are all done perfectly. The script and direction are supplemented by an excellent performance by Hemmings. Lots of Hitchcock stylings, but he takes suspense and horror to places Hitchcock never went.
