“THOROUGHBREDS”

****

(R, 1:30)

They say there can’t be a good story without a good villain. In his dazzling debut, director and screenwriter Cory Finley aims higher. “Thoroughbreds,” a smart, amoral suspense comedy about the high price of having it all, gives us villainy in stereo.

With double the standard badness quota, the film isn’t just good. It’s excellent, en route to a rabid cult following if not more. Watching this is a reminder that seeing wicked people do wicked things can be one of cinema’s greatest pleasures.

Thoroughbred is a term that’s used to describe to both valuable race horses and flawless young guys and girls. Here, it’s a clever bait and switch. Anya Taylor-Joy and Olivia Cooke play Lily and Amanda, two ostensible heroines with fresh-faced beauty and polished manners who would skin Dalmatian puppies for a fur coat. The teens live in an upper-crust section of Connecticut where smaller mansions have fewer than two dozen rooms. The old boarding school chums reconnect after some years apart, spending weekend afternoons inside Amanda’s perfect home, studying for a college prep test.

They’re together in a form of weekend detention designed by their overscheduled parents. Amanda has been a social leper since creating a scandal involving her horse, not that she was all that popular before. Lily killed her own Ivy League dreams and was put under house arrest by her totally uncool stepdad after an embarrassing episode of plagiarism. As the castaways grudgingly restart their old friendship, things get insidious.

We learn that icy cool Amanda isn’t just acting detached; she really is. She is so blasé about the difference between make-believe and real life that she performs smiles in the mirror and practices crying at will by using “the technique” starlets used to weep in old black-and-white movies. She lacks “any feelings ever,” whether it’s joy or loneliness or guilt. “I have a perfectly fine brain,” she announces. “It just doesn’t contain feelings. It doesn’t mean that I’m a bad person — just that I have to try harder than other people to be good.”

Her ambition is to “Steve Jobs my way through life,” a sample of Finley’s knack for writing — and his cast’s gift for delivering — comically robust strains of cynicism.

The quieter of the two, but hardly the lesser character, Lily has lots and lots of feelings, and her own brand of performance art. She dresses and behaves like a demure preppy debutante because playing the brat is undignified. Still, she is concealing feral resentments against Mom’s new husband, Mark (Paul Sparks, impressively unlikable yet far from evil).

We see a photo of him standing self-importantly beside a lion he killed and another posing with a samurai sword, which he keeps on the wall of his study. He wears skintight bike shorts, treats his wife like a servant and makes droning sounds hour after hour on his rowing machine. When pragmatic Amanda asks, “Ever think about just killing him?” Lily is aghast, until she’s atingle. They’re hardly perfect friends, but as co-conspirators they complement each other perfectly.

Executing their task requires a flunky to play the hit man, and the girls find a magnificent simpleton in Tim (the late Anton Yelchin in one of his final roles). He’s a nickel-and-dime drug dealer of humble background who imagines that with a decade of hard work and determination, he could take charge of the local market for dope — and move out of his dad’s home for a place of his own.

This Horatio Alger hero in reverse has facial bruises where his high school clients beat him up, but he’s ever ready to put his swollen nose back to the grindstone. Yelchin makes Tim a hilarious blend of ambition, anxiety and absurdity, a born loser with generations of disappointment in his DNA. Even his disheveled hair looks worried.

Finley’s female leads, in contrast, are larger than life, vibrant with energy, and, like sharks, always moving forward.