Aside from Anna Paquin, the film also stars Lena Olin, Iain Glen, Giancarlo Giannini, Fele Martínez, Stephan Enquist and Fermín Reixach.
Here's a quick plot synopsis
Three weeks ago, just before the lunar eclipse, American teenager Regina (Anna Paquin) and her family moved into a charming old house in the remote Spanish countryside. Since then, nothing has been the same.
Day by day, a strange force seems to be pulling the family apart and Regina is the only one brave enough to search for answers. But she is about to discover the answers to all her questions lie deep within the walls of their new home.
Something has been waiting here for her family's arrival. Something ancient and wicked. Something looking for retribution. A force as bottomless and hungry as the dark itself. Now, darkness is closing in on Regina's family, and she's their only chance for survival.