“The Gift” (STX) takes its time unwrapping. What begins as a psychological thriller eventually reveals itself as another entry in the revenge-fantasy genre: Someone wronged back in high school wreaks elaborate self-styled “justice” on a smugly successful former classmate.

The story includes a few competently delivered seat-jumping shocks, since writer-director Joel Edgerton — who also plays the mysterious retribution-seeker, Gordo — happily embraces some horror cliches in the midst of his understated style.

Simon (Jason Bateman) and Robyn (Rebecca Hall) have moved to the West Coast from Chicago because of Simon’s exciting new job as a corporate security expert. They’re both anxious for a new start.

In Robyn’s case, that means re-launching her freelance interior-design career while recovering from a miscarriage.

Time, Simon insists, heals everything;

Not so fast, Simon. On their first outing to a hardware store, the spouses encounter the mumbling Gordo, an acquaintance from Simon’s school days.

Socially awkward Gordo has had a rough time of it as an adult. The military didn’t work out for him, and he has a bit of a criminal record.

He’s also generous to a fault, or so it seems. He starts dropping by the couple’s expensive house with gifts, leaving presents at the front door when they’re not home.

He even — cue the spooky music — drops in on Robyn when she’s alone.

Robyn, sensitive and compassionate, doesn’t find Gordo all that annoying, and is initially suspicious of Simon’s damning descriptions of him. She’s briefly on her husband’s side, however, after Gordo invites the duo to dinner at a fancy home that turns out not to be his.

Yet, even as she learns the awful secret of Gordo’s past, Robyn also discovers that her manipulative husband has a dark side of his own.

The conclusion is marred by several logical flaws as well as by the misogynistic notion that Robyn can somehow be made to represent a sexual “gift” herself.

The film contains a vengeance theme, some physical violence, an implied sexual assault, adult banter, a couple of uses of profanity and frequent rough and crude language. (A-III, R)