Exquisite Corpse Trailer (2010)

Nicholas is one of the most brilliant young neuroscientists at his medical school and is on the verge of a breakthrough. He just discovered a serum that can bring a dead laboratory rat back to life. He should be reveling in his new discovery, but has other things on this mind.

He is in love with his long time crush, Sophia, and has invited her on a weekend trip to a mountain cabin, the perfect setting to express his deep feelings for her. He finally gets up the nerve to tell her how he feels about her, and to his surprise she tells him that she feels the same way. Life just can't get any better.

But Nicholas's elation is short lived. His world comes crashing down when Sophia goes for a swim and drowns in the lake, taking away his hopes of a future with her. But wait, what about the serum... could it work on a human? He will need to extract oxytocin from another human subject in order test his theory. He invites a prostitute back to his apartment, and kills her and it works. Sophia is brought back to life. She seems OK at first, but not all is well. She has lost a part of her humanity, and it seems that the results of the procedure are only temporary as she dies again after a short time.

In order to keep Sonia alive, Nicholas must kill again and again to keep injecting the serum into Sophia. This vicious cycle only lasts for one day, and they both descend into madness and horror, until there is only one way out.