A scientist at a Florida University accidentally creates a "rage virus" while conducting experiments to restore dead brain tissue in baboons. The virus soon spreads.
After being announced dead and taken to a morgue, Jason Voorhees spontaneously revives, escapes from the hospital, and stalks a group of friends renting a house in the countryside near Crystal Lake.
A series of gruesome accidents plague a small American farming community in the summer of 1935, encircling two identical twin brothers and their family.