Insomnium

As George recovers from hiking injuries, his roommate Phin unexpectedly begins sleepwalking throughout their shabby Los Angeles apartment. As George’s obsession with Phin's increasingly disturbing behavior intensifies, his own life slowly disintegrates and he suspects that Phin has become possessed by unknown entity. Suspicious that his landlord, Mr. Romanovsky, is guarding a dark secret; George investigates and makes a startling discovery. Now with more questions than answers, George struggles to unravel the truth before it consumes him and destroys Phin. It's time you knew about the girl upstairs.