Clive and Elsa, romantically involved celebrity scientists (Adrien Brody and Sarah Polley), have been mixing animal DNA in order to create strange mutant creatures. When they throw some human DNA into the mix, the resultant creature is an animal/human hybrid named Dren—and she just might kill you. Vincenzo Natali’s insane movie takes the boundaries and barriers that have made horror films so bland and routine in recent years, and blasts them with steel-toed boots and sledgehammers. Mainstream audiences generally aren’t expected to deal with horrific material like this; it’s the sort of horror usually left for genre nerds and geeks.