I Don't remember much... but there was a boy, who was involved with some Hippies, who wanted to save some trees... they were living in tunnels underground to hide from the police etc.. . the boy has some flashbacks, about swimming in a river while having sex with a girl... who from memory, is swept over a waterfall & dies after? Anyway he is hiding in this tunnel with a girl & they have sex... It's raining & there is a mudslide & the girl dies... He is carried away by rescue workers, naked & screaming for the girl? Any ideas of what it was called?