The only thing that annoyed me was...
I enjoyed the film and thought it was very well made. But the one scene that annoys me is the scene where Megan does not realize that Jonathon has gotten out of the water, and one of the twins, grabs, feels and touches her with his hands, she at first assumes it's Jonathon, until she see's him on the shore, at this point she begins to panic and then swims to safety, seeming terrified.
But the fact that she or none of the others seem to believe this is a big deal makes no sense to me. The next scene we see her in, it is night and she is dancing around the camp fire listening to music. She seems in no way worried or traumatized by this incident.
If this had happened to anyone else in the world they would have made a big deal out of it and would have encouraged the others to leave the area. But she doesn't really seem that bothered by it. As soon as the event is over, it no longer worries her. If they had her at least trying to convince the others that this had happened and that they should leave the area, I would have been be ok with it, but the fact that she does nothing after the initial moment of fear and shock caused by the incident seems really silly to me. Also when Jonathan went missing you think she may have thought there may be some connection between the two events (to be fair they didn't really know he was missing at first, but if she knew there may be someone strange out there she wouldn't have encouraged him to go out in the woods alone to find her make-up, even if she was somewhat of a narcissist).