The waitress Frances (Chloë Grace Moretz) find an expensive handbag on the subway, it contains the owner's id and Frances therefore contacts her to return the bag. The lonely widow Greta, the owner of the handbag and Frances become friends. But after a while Frances realizes that something is not right with Greta, but then it's to late. The only one who can save her is Erica's best friend, but will she succeed? Andreas Samuelson writes in QX that Huppert is brilliant as the piano-playing psychopath Greta. Nina Asarnoj at Kulturnytt describes the film as a "Bridget Jones for horror lovers (...)".