Higurashi no Naku Koro ni Kai

Synopsis

The events of the dam incident are shown, including when the Houjou family first antagonized themselves against the Sonozaki family and Hinamizawa residents. It is revealed that the dam construction manager was murdered and dismembered by his own construction workers when he (the manager) caught the men drinking after work and went on a rampage. Meanwhile, Takano and Dr. Irie had been researching the Hinamizawa Syndrome at the institute, but they needed a live specimen to prove the linkage between a parasite and the onset of the syndrome. They eventually utilized one of the construction workers (who had succumbed to a state of psychosis) responsible for the murder of the construction manager as a live specimen. In another flashback, Satoshi talks with Dr. Irie regarding how he wants Satoko to stay at the clinic longer so that Satoko won't fight with her aunt at home, simultaneously lifting a burden off of himself. During all these events, Hanyuu feels helpless and apologetic, but years later Hanyuu and Rika eagerly await the arrival of the one person who will be the key to bringing an end to the enemy's intentions.

(Source: Wikipedia)