Good performances (spoilers)...

Good performances all around (especially from the leads) saves this from being unwatchable. The boring plodding aspects of the film are enough to turn most people away but again things are saved by the actors.

The dream sequences\hallucinations add nothing to the proceedings and only serve to add an aura of "artsy" about a film that is not at all cinematic art.

The triumvirate of Natasha, Chloe, and Meg ground the film and keep you interested as the story meanders along until the final ten minutes. Honestly, for most of it I wondered how bad Natasha's character had to smell not changing her clothes or bathing for days\weeks! That's how boring the movie was!

As stated it picks up but not until the very end. During the rest you'll be asking yourself why this was called a horror movie or a scifi movie. Zip leads you to believe something other than a "bad trip" is happening to the lead character.