IGX

http://www.imdb.com/title/tt0464141/ (Don't read the spoilers at IMDB)

Just watched this tonight on Netflix. Very, very well done Spanish-lang horror film. (G. Del Toro was the Ex. Producer, BTW).

Creepy vibe, good mystery, and one horrible, shattering moment towards the end that means I must insert the PARENTAL WARNING:

If you are a parent, watch at your own risk. That part may fuck you up.

In its setting, its lack of cheap gore, and its excellent atmosphere it's very reminiscent of the old George C. Scott film "The Changeling" (which is also worth a rent, BTW.)