Refreshing.
When a movie starts with some college students packing for their weekend at a cabin in in the woods you are instantly set to predict a bad film. Something will go wrong, they will be trapped, every one will die one by one until the hot girl is the last survivor. One difference; technically the film starts in some form of scientific facility. It is a brief scene that make little sense until the mid-film, but that is where you realise this is not a cliché horror, but a unique and interesting film where many unexpected things take place.