The Happy Ending:
Teenager Hayley Stark (Ellen Page) makes Jeff Kohlver (Patrick Wilson) pay for his ill deeds by forcing him to step off the edge of his roof and hang himself.
The Depressing Implications:
Hayley actually get away with what she did? It might look like a suicide, but there has actually been a murder here - and the police tend to investigate that sort of thing.
How long before they track her IP address?
Also, Kohlver was definitely a monster, but we pity his poor friends, who have been completely kept in the dark up until the events of the movie.
It's going to be an awkward funeral, that's for sure.