"Kristen" is a claustrophobic thriller/horror about Kristen Welling, a fragile woman in her late twenties, who, on January first when cleaning the mess of last night's party, gets terrorized by an unknown person. Kristen was supposed to do this with the help of her boyfriend. But he doesn't show up or picks up his phone. In the meantime someone keeps calling Kristen asking her to step outside. This person seems to know all about her. More than anyone alive should. And when the first drop of blood is spilled and Kristen's world turns into a nightmare she has to find out who is doing this...and why.