Grade: B-

Lovers of basketball, especially one-time players who have abandoned the court for the bleachers with the passing of years, will probably be the ones who most enjoy “Uncle Drew.” But the movie’s attraction should go beyond that base. It’s a hoops fantasy that hews closely to the standard tropes of underdog sports stories, but does so with a gleeful irreverence that should make it surprisingly enjoyable even for someone who’s never dunked, or even dribbled.

The script by Jay Longino works off a series of Pepsi Max commercials made by NBA star Kyrie Irving, in which he donned old-age makeup to punk young street players. Here crotchety Drew is a legend among old-timers who remember his sensational pro play, as well as the fact that his pre-NBA street team imploded shortly before they were to compete in Harlem’s famous Rucker Park tournament. Since then he’s disappeared into anonymity, occasionally popping up to humiliate hotshots as the commercials showed.

Among those who barely know the legend is Dax (Lil Rel Howery), who as an orphan kid (Ashton Tyler) was enthralled with basketball but stopped playing after his potentially game-winning shot was blocked in the Rucker finals. Now working at Foot Locker, he’s coached teams in the tournament for years, always losing to squads coached by his nemesis Mookie (Nick Kroll), the kid who blocked that shot. This year, however, he’s fielding a team headed by the unstoppable Casper (Aaron Gordon of the Orlando Magic, who on the evidence here shouldn’t give up his regular gig for acting), and his shrewish girlfriend Jess (Tiffany Haddish) is counting on the prize money to fill all her shopping needs.

Of course Casper is stolen away by Mookie (who also steals Jess, though why is anyone’s guess), and desperate Dax looks up Drew, who is busy besting a “youngblood” poseur on a street court. Drew agrees to come out of seclusion to teach modern-day showboaters how the game should really be played (for love, not money), on condition that he put together his old team for the Rucker. They’re all septuagenarians like him: Preacher (Chris Webber), who’s bothered by prostate problems and whose wife Betty Lou (Lisa Leslie, formerly of the WNBA) is adamantly opposed to his playing again; Lights (Reggie Miller, who played with the Indiana Pacers through 2005), who’s legally blind; Boots (Nate Robinson, who had a ten-year NBA career), a wheelchair-bound guy who has to be snatched from a retirement home; and Big Fella (Shaquille O’Neal), who runs a martial-arts dojo for kids and hates Drew for having slept with the woman he loved on the night before their Rucker championship game. Joining the grizzled crew is Boots’s sweet granddaughter Maya (Erica Ash), who will obviously serve as romantic interest for Dax.

What follows is entirely predictable and equally implausible, from the reckless chase in which Lights must drive Drew’s old-school van backwards to outrace Betty Lou through the final game, in which Dax will have to take the court when one member of his team is injured. (Don’t worry: before that everybody gets to shine, including Leslie.) You might also find high-strung Howery, who comes across as a cut-rate version of Kevin Hart, a little exhausting. The same adjective applies to Kroll’s shtick as the inexplicably nasty Mookie and Haddish’s shrieking turn as gold-digging Jess.

Nonetheless the movie works reasonably well because Longino occasionally drops in good bits of business like Drew’s dismissal of contemporary music as “rappity hippity hop” or Dax’s description of Big Fella as looking like Wolverine’s grandfather, and because Stone trades the lethargic pacing he brought to his earlier, similarly over-the-hill sports comedy “Mr. 3000” for an approach that’s more zesty and hectic. A crisp editing job by Jeff Freeman and Sean Valla helps.

That’s especially true in the montages of court action that serve as the movie’s final act, in which the oldsters get to show that neither their bodies nor their skills have entirely atrophied, but also in sequences like one where Preacher threatens to baptize a baby as though he was preparing to dunk a ball. Even the seemingly inevitable dance-off between the geezers and a bunch of young dudes and their girls at a Harlem club isn’t as awful as one might have expected.

Most importantly, Irving and his court cohorts seem to be having a great time, and their enthusiasm for the ridiculous plot is infectious (O’Neal is even willing to do a bare-bottom shot). The old-age makeup isn’t remotely convincing (although, from the clips that accompany the final credits, it took a lot of effort to apply), but the very cheesiness is part of the joke, as is much of Douglas J. Meerdink’s production design (like the design of Drew’s old-school van, down to its 8-track tape player). The camerawork by Crash is no great shakes, but it comes alive in the scenes of court action.

No one will mistake “Uncle Drew” as a sports movie classic. But as a feature-length riff on a slim commercial premise, it goes down as easily as a Pepsi Max.