It appears to be about serial murders and a detective, Takabe chasing down the killer. The mystery is that when the murderers are caught they have no memory of what they did. Eventually it narrows down to one mad man (?), Mamiya who mostly refuses to answer questions, instead asking them. The detective who at first radiates a demeanor of calmness, but as we learn his wife who he truly loves has mental health issues which are very stressful. He loses emotional control with Mamiya who claims to know what a burden she must be.
The film is designed to keep you on edge all the way through. Bong Joon Ho, famous for "Parasite" (2020) claimed that this movie was one of his top ten. http://www.therealjohndavidson.com/2020/09/parasite-breaks-oscar-tradition.html It seemed worth pursuing for a deeper understanding. An interview with Ryusuke Hamaguchi (who admitted to learning from Kiyoshi Kurosawa) http://www.therealjohndavidson.com/2022/07/drive-my-car.html and other DVD interviews did offer some rationale.
There were several murders that are each very abrupt and gruesome. The first at the very beginning appears to be between a prostitute and a customer who unexpectedly hits her repeatedly with what looks like a pipe. More follow at unexpected intervals.
The original title was "The Missionary" and it was referred to in the
script as the police were speculating on Mamiya' motive. Some felt he
was a missionary for the beliefs of Franz Mesmer. He was an early
precursor to the notion of hypnosis.
The writer director, Kiyoshi Kurosawa had noticed that after a murder in the news neighbors were questioned and invariably said the killer was normally a nice person. Reporters mostly expressed the idea that the killer was hiding their intent. Kiyoshi felt a nice person could kill which was an underlying premise for the script. Kyoshi also admits that he didn't consciously do some of the things attributed to him, and in some cases "retrofitted" later thoughts into his explanations. He has been noted for his unique use of space where he felt what happened outside the frame was also important. There were a lot of hypnotic references such as flashing lights and water flowing.
One of the actors (likely Masato) commented that Kiyoshi did not use rehearsals a lot and more for the crew who needed to know their positions. Kiyoshi ate his lunch alone most often without cast or crew so that he could sort out the issues of filming.
He once won a scholarship to the Sundance Institute. He was also for a time a professor at the Tokyo University of the Arts. Kiyoshi has 61 credits as director, 54 as writer and 16 as actor including "Tokyo Sonata" (2008).
Music was provided by Gary Ashiya who has 42 credits. It was remarked that music was only played during the beginning and at the end. In between ordinary household sounds dominated with Kurosawa commenting that an empty laundry dryer was especially annoying.
Tokkusho Kikumura was the cinematographer with 47 film credits.
Kan Suzuki was the editor with 56 credits.
Tomoyuki Maruo, the production designer played a role in setting up this film. He had worked with Kyoshi when they were both doing videos. A common problem was low budgets. This problem was solved for "Cure" as more money was made available. Up until this time film makers could not afford sets and used locations which were often run down. Despite higher budgets the locations practice was carried on for this film. Tomoyuki has 50 credits as Art director and another 29 as a production designer, including "Tokyo Sonata" (2008).
Koji Yukusha played Takabe. He was a popular actor which possibly accounts for the need of bigger than video budget. In that same year 1997 he was he leading man in two other noteworthy films, "The Eel" (1997) that earned an acting award at Cannes and "Shall We Dance" (1997) that was a very popular international film. Check the third paragraph http://www.therealjohndavidson.com/2015/03/japanese-movies-are-more-than-godzilla.html Koji has 109 credits including "Tampopo" (1985), "Memoirs of a Geisha" (2005)"Babel" (2006), and "The Third Murder" ((2017).
Masato Hagiwara played Mamiya. In trying to recruit him for the part Kiyoshi asked him to watch "And Life Goes On" (1992), a Turkish film by Abbas Kiarostami. He is another popular actor with currently 134 film credits, including "The Journalist" (2022). Check http://www.therealjohndavidson.com/2022/01/the-journalist.html
"Cure" is a unique film and if you don't get too upset with gruesome violence you might enjoy it, even be impressed.