In the 80's, after seeing his father and lumberjack foreman being hit by a protestor against the deforesting and arrested by the police, the boy Gus kills the protestor with a chainsaw. In the present days, Samantha, who is traumatized after being abused by her former boyfriend Jimmy, travels with her pothead friends in a van to the American Free Love Festival, a rock-and-roll concert in the woods. Near the location, they are assaulted by three local hillbillies, but they succeed to arrive in the festival. Meanwhile, Mayor Hal Burton and Deputy Buzz Hall try to give a minimum of organization to the event. However, a deranged psychopath serial-killer wearing a mask of Ronald Reagan uses an ax to kill the pacific stoned hippies. 
 
http://www.imdb.com/title/tt0760187/