“Hot Tub Time Machine”

Directed by: Steve Pink

Starring:… “Hot Tub Time Machine”

Directed by: Steve Pink

Starring: John Cusack, Clark Duke, Craig Robinson, Rob Corddry

MGM Studios

B+

Film scholars, cinephiles and audiences looking for more out of movies than just entertainment, beware the following lines: “Must be some kind of … hot tub time machine …”

Fortunately, the rest of us will get exactly what we’re expecting out of the blatantly titled “Hot Tub Time Machine” — a funny, dumb and good-natured comedy with about as much longevity as hair metal.

It seems almost redundant, but here’s the plot: A hapless insurance salesman (John Cusack) and his two middle-aged buddies (Rob Corddry and Craig Robinson) travel with Cusack’s young nephew (Clark Duke) to a ski lodge they used to frequent in their youth, hoping to reclaim some shred of the free-spirited past.

Much to their dismay, they arrive to find the surrounding town boarded up and the lodge in a sorrier shape than their lives.

All is not lost, however. Their room’s hot tub, into which they stumble in a last-ditch effort at fun, is also — spoiler alert — a time machine.

After a night of drunken debauchery, they awake to find themselves in that comedic fantasyland of frizzy haircuts and cassette players — 1986.

But far from being handed a second lease on life, the men have to ensure their night goes exactly as it did on that date in the past, or else, as a mystical Chevy Chase warns, some butterfly effect will trigger and in the words of Clark Duke, “We’ll make Hitler president or something.”

From then on, the film follows a cycle similar to the recent crop of R-rated comedies: an increasingly ridiculous spree of slapstick, drugs and genitalia jokes.

Throw in a few feel-good song numbers (hope you like Mötley Crüe) and a few cameos and what you’ve got is a foolproof, albeit predictable, comedy — which, for anyone who’s seen the trailers, should be expected.

The film’s greatest strength is its returning gags, including, but not limited to an ever-present squirrel, a one-armed doorman, a “Red Dawn”-worshipping jock and of course, everything that was ever popular in the ’80s.

The acting ranges from memorable to solid. On the “memorable” side of the spectrum is “The Daily Show”-vet Rob Corddry, who inhabits the archetypal belligerent a**hole disturbingly well.

Other performances pull their own weight. Craig Robinson is lovable as always, Cusack is a sympathetic straight man, and Clark Duke, while far from stealing the show, channels the “awkward adolescent” as well as anyone.

The only aspect of the film that feels strained is its half-hearted attempt to interject a message about fate and “embracing the chaos” into an otherwise absurd setting.

If I were director Steve Pink, I’d make sure to slash anything that elevated “Hot Tub Time Machine” above a celebration of the stupid.

But in a film so otherwise gleefully resistant to meaning, such preaching was but a minor blip in the fun.

Like its predecessor, “Snakes on a Plane” (2006), the genius of “Hot Tub Time Machine” is its marketing strategy.

There’s not a soul in the world that’s seen the “Kick Some Past” posters and still thinks this movie will be about anything more than a hot tub that’s also a time machine.

If you’re looking for an intellectual tease, “Shutter Island” might make for a more rewarding outing.

But if you want a giggle-inducing, f-bomb-dropping romp with enough ’80s references to make even those born in the ’90s feel nostalgic, then as the lovably inane trailers assure us, get ready to kick some past.