Review: ‘Behaving Badly’ certainly does

“Behaving Badly” is a dreadful sex comedy that gets worse and worse as its dopey story snowballs into relative incoherence.

The film’s starry supporting cast is proof positive that actors — even onetime Oscar nominees — just want to act. In anything.

Hapless high school student Rick Stevens (an offhanded Nat Wolff from “The Fault in Our Stars”), who lives in a world that seems populated by rejects from TV’s “Arrested Development,” makes a bet with the dweeby son of a local mobster that he can bed class beauty — and all around good girl — Nina (Selena Gomez) in short order.

But this wager is merely the nominal engine for Rick’s already fraught life to take a series of nutty twists and turns, many of which feel as if they’ve been concocted on the fly by director Tim Garrick, who adapted the script with Scott Russell from the 2000 novel “While I’m Dead ... Feed the Dog.” It all adds up to a randy groanfest that, er, climaxes too quickly and sticks us with an interminable, falsely earnest third act.

Though Rick is a largely reactive character, he at least feels somewhat of this planet. Most everyone else, however, is of the broad, one-note variety; dumb people who do dumb, under-examined things. The roster includes Rick’s suicidal, alcoholic mom (Mary-Louise Parker, who also pops up as his fantasy guardian angel), absentee dad (Cary Elwes), closeted gay brother (Mitch Hewer) and whorish sister (Ashley Rickards); Rick’s best friend’s (Lachlan Buchanan) oversexed mother (an embarrassing Elisabeth Shue, said Oscar nominee), a kinky strip club owner (Dylan McDermott), the world’s worst priest (Jason Lee), a leggy lawyer (Heather Graham) and others.

It’s an egregious waste of talent — and your time.

“Behaving Badly.”

MPAA rating: R for crude sexual content and language throughout, some graphic nudity, and drug material.

Running time: 1 hour, 38 minutes.

At AMC’s Universal Citywalk Stadium 19, Universal City.