The Most Terrifying/ Help Explaining SPOILERS

The cell phone footage is some scary *beep* I've seen this film three times now and every time my heart is pounding anticipating the cell phone footage - love it!

But yes that's right, she sees the ghost of her future self. The official term would be a doppelganger - which is essentially a 'double' of a living person. There are lots of interesting (and alledgedly true) stories from people who claim to have seen a doppelganger, so if you're interested in the phenomenon you should check it out!

Quote wikipedia: 'Doppelgängers are often perceived as a sinister form of bilocation and generally regarded as harbingers of bad luck. In some traditions, a doppelgänger seen by a person's friends or relatives portends illness or danger, while seeing one's own doppelgänger is an omen of death.'

I don't think that Alice was drowned by her future ghost, rather, I think that her future self manifested itself to WARN her of her death. It seems logical to me that if a ghost of yourself appears in front of you, it is not there to harm you, rather, it has manifested itself to protect you. Perhaps the doppelganger is a sign of the inevitability of her death (which is how Alice saw it), but I think the ghost was there to try and stop her from swimming in the lake, to avoid drowning.

Somewhere on this board I offered a theory that the neighbours had something to do with her death (because of the sex tape), and that the ghost was warning her of the neighbours intentions to cause her to drown.