Relativity Media has released a new trailer for director Mike Flanagan’s (Absentia) new horror film Oculus.  The pic stars Karen Gillan (Doctor Who) and Brenton Thwaites as siblings who set out to prove that an ominous mirror is responsible for the death of their parents 10 years prior, as well as the deaths of countless others over the centuries.  The film looks to have a fascinating structure, as the lines between the past and the present are blurred and twisted until they become a part of the overall horror conceit.

Hit the jump to watch the new trailer.  The film also stars Katee Sackhoff and Rory Cochrane.  Oculus opens in theaters on April 11th. [Update: We've also added a new poster and images to the article.]

Here’s the official synopsis for Oculus:

Ten years ago, tragedy struck the Russell family, leaving the lives of teenage siblings Tim and Kaylie forever changed when Tim was convicted of the brutal murder of their parents. Now in his 20s, Tim is newly released from protective custody and only wants to move on with his life; but Kaylie, still haunted by that fateful night, is convinced her parents’ deaths were caused by something else altogether: a malevolent supernatural force¬¬ unleashed through the Lasser Glass, an antique mirror in their childhood home. Determined to prove Tim’s innocence, Kaylie tracks down the mirror, only to learn similar deaths have befallen previous owners over the past century. With the mysterious entity now back in their hands, Tim and Kaylie soon find their hold on reality shattered by terrifying hallucinations, and realize, too late, that their childhood nightmare is beginning again...

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