Two teenage girls, one a self-admitted sociopath, the other a spoiled schemer, conspire to commit murder in Cory Finley’s brilliantly incisive Thoroughbreds. It’s hard to tell whether the fragile Amanda (Olivia Cooke) and the self-assured Lily (Anya Taylor-Joy) are ever truly friends, or whether they’re ever showing each other their true emotions. Part of what’s captivating about Thoroughbreds is the way that its two main characters are simultaneously completely open and insidiously manipulative, playing on each other’s weaknesses in ways that they themselves don’t necessarily even understand (with every feint and bluff masterfully conveyed by the movie’s stars). At the same time, they share a genuine, affecting bond as two misfits who don’t subscribe to the moral code of their rigid private-school society. Finley isn’t interested in judging them, and he fills the movie with deadpan humor and a percussive, unsettling musical score that keeps the viewer constantly on edge. His camera roves through Lily’s cold, cavernous suburban mansion in a series of long takes, and the movie often delivers emotional reveals via rack focus. It’s meticulously composed and utterly vicious, just like its two fearsome protagonists.