Every dance number in "Step Up All In," whether it takes place in a bar, a boxing ring or a Las Vegas gladiatorial arena, is a battle sequence. The mostly male crews – whose routines are a mix of breakdancing, Bob Fosse musicals and Chippendales routines – mime hitting and shooting each other. In one impressively vulgar moment, the dancers simulate urinating on their opponents.
The moral of all this macho territorial marking? That dancing is love.
As the title advertises, the latest in the "Step Up" series brings back all the audience favorites from the previous four installments. All the ones that are affordable, that is. Channing Tatum (2006's "Step Up") is not in the company, although the story still turns on a slab of sullen beefcake: Ryan Guzman, whose Sean returns from 2012's "Step Up Revolution."
The first "Step Up" was set in Baltimore, where dance was presented as a rousing if unpersuasive route off the mean streets. This one travels to Nevada's casino capital, and the movie embraces the upscale tawdriness of Vegas with all the ardor of a tourist board commercial. There's more glitz and even less story.
In the opening sequences, Sean's dance crew – called the Mob – gets fed up with not getting steady work in Los Angeles and heads back to Miami. Sean stays behind, so when the always-unshaven dancer learns of a major international contest being held in Las Vegas, he must assemble a new team of hoofers. There are a lot of them, but the only ones with more than a few lines are shaggy-haired Moose (Adam Sevani, a "Step" regular) and bare-midriffed Andie (Briana Evigan, from "Step Up 2: The Streets").
The newly assembled crew is dubbed LMNTRIX (say "elementrix"). It faces many teams, but again only two count: Sean's old Mob and L.A.'s Grim Knights, who already have reason to hate the newcomers. The Grims are led by Jasper (Stephen "Stev-o" Jones), who's not merely hot-tempered; in one of several utterly unsurprising developments, he turns out to be corrupt as well.
The showdowns are vigorous and intricately choreographed, with more elaborate costumes and props than the low-budget LMNTRIX might be expected to muster. First-time director Trish Sie, a music-video veteran, is more interested in spectacle than character, as she demonstrates even when nobody's dancing.
The 3-D effects add little, although occasionally the dancers throw something in the audience's face. Sand and glass are the most hostile.
There's also plenty of acrimony between Sean, who wants to win, and Andie, who just wants to dance. He has a big move planned for her, and she's scared it will damage her trick knee. So why doesn't he do the routine with another female dancer? Because then Andie wouldn't be in Sean's arms when it comes time for the squabbling to turn to smooching.
Because, you know, dancing is love.