The plot of Cory Finley’s Thoroughbreds must have been an easy sell from a distance: two troubled girls plot the murder of a vicious step-father, entangling a low-level drug dealer along the way. It is a variation on tropes that are so familiar—patricide, the wicked step-mother, murder-for-hire—that dozens, if not hundreds, of movies past could fill its shoes. But this careful and reserved movie pulls itself ahead of the pack with its deliberate choices in tone and tempo.

Set on the Gold Coast of Connecticut, Thoroughbreds takes place in the upper echelons of society. Amanda (Olivia Cooke) and Lily (Anya Taylor-Joy), former horseback riding friends, have grown apart since the death of Lily’s father but are reconnected when Amanda needs help studying for a standardized test. Very early on, we learn that Amanda is a sociopath: her therapist has diagnosed her simply by flipping to random pages in the DSM-V. Amanda’s emotional vapidity, though, ironically helps to reveal Lily not as the Stepford-Wife-in-training, but as an emotionally lost soul who has become increasingly unhinged when her mother remarried after her father’s death.

Mark (Paul Sparks), the stepfather, is an overbearing and controlling individual, a big game hunter and avid juicer. Lily does not like the way he treats her nor her mother. His abuse is mental and emotional, though there are suggestions that he’d like to physically punish Lily or just send her away. Proposed as a question first by Amanda, then as a possibility by Lily, the pair blackmails local drug dealer and statutory rapist Tim (Anton Yelchin, in his last movie role) into killing Mark. When that plan fails, Lily takes matters into her own hands.

Because Thoroughbreds trods on ground that has been travelled many times before, the details of the plot are secondary to how they are approached, and this movie hits each marker with almost surgical precision. In the same scene where Lily is first exploring the depths of Amanda’s inability to feel, the cinematography positions the two at opposite sides of the screen facing outward. Although subtle, this gives the feeling that the two are not seeing eye to eye, a feeling that is recreated on the theatrical poster and elsewhere through the use of mirrored sunglasses.

This mirroring effect is important in masterpieces like Bergman’s Persona or Lynch’s Mullholland Drive where duality is revealed eventually to be a singularity. Here Cory Finley as both writer and director uses the mirroring to juxtapose Amanda and Lily, heightening their differences. In one scene, Amanda attempts at teaching “the technique,” which is her way of crying on demand. Lily fails, but later cries real tears for herself after being lambasted by Mark for her lack of empathy. Amanda thinks Lily is using her technique, but it’s just her inability to read emotion in others.

Like the cinematography, disjointed understanding creates a kind of tension between the two, an absurd dance. A haunting score by Erik Friedlander, an accomplished avant-gardist, that has key elements of Varese’s atmospherics and the prepared pianos of John Cage, with the pulsating beat of Modernism, keeps you absorbed on the screen and the story. The score subtly colors the visuals, creating tension and uncertainty in a way that does not create attachments to the music itself. This is part of a modern trend in scoring—think of Anya Taylor-Joy other recent movies The Witch and The Blackcoat’s Daughter—where mystique trumps memorabilty.

Amanda and Lily are viewed as products of their world—indoor home swimming pools, elite educations, and the titular thoroughbred horses that they rode together when they were younger. They too are thoroughbreds, if that isn’t too on the head; both have an inability to cope with the world around them, a metaphorical broken leg.

The girls become, over the span of the movie, each others’ broken mirror. It’s easy to see Lily’s final plan as her re-imagining of what she thinks Amanda would do in her place. Amanda, for all her dispassionate detachment, accepts that she might never be fixed or cry real tears of sadness. She goes along with Lily presumably for the same reasons that she euthanized her horse: in her mind it was the right thing to do. By the end, the viewer isn’t exactly rooting for either Amanda or Lily, but because of incredible acting skill throughout the film, we are right there with them, flaws and all.

As Thoroughbreds goes through many obvious hoops and tired plot lines, it’s incredible that it reaches such a satisfying ending—and that it was a satisfying movie as a whole. It’s a very worthy first film by Cory Finley, who masterfully turns what could have been a dead-in-the-water thriller into something worth revisiting. But these tropes have been tropes for more than just the last century of film—we’ve been killing our fathers for centuries—but better a movie like Thoroughbreds to get greenlighted than to have a remake of Strangers on a Train or Night of the Hunter. It’s nice to have fresh—and vicious—original stories coming to the screen, instead of rolling reboots.