Anna Kendrick is a cutesy, naive woman, with a nervous laugh and a pension for going “uh” and “yeah.” And in this film, she plays a Mommy Blogger, someone who makes videos on how to cook brisket and make friendship bracelets. One day, when she goes to pick her son up from school, she meets Blake Lively, the mother of one of her boy’s friends, who invites her over to her incredibly stylish house for some martinis. Lively is everything Kendrick isn’t–assertive, foul-mouthed, impeccably dressed–which makes her fascinating to the latter. That’s probably why Kendrick winds up doing everything Lively tells her to including picking her son up from school one day. This turns into more than a “simple favor” since Lively doesn’t return for several days, and the police suspect foul play, because she and her husband, Henry Golding, were having financial and marital problems. Kendrick doesn’t believe this, however, even after the cops find what they think is Lively’s body, and so does some digging of her own, uncovering some shocking, albeit rather silly, answers.