Rock in Rio USA, the new-to-America music festival that wrapped Saturday after two often-incoherent weekends here, needs to figure out some things if it wants to compete in the rapidly growing festival scene dominated by the likes of Coachella and Bonnaroo.
For starters, the event — a splashy expansion of the festival founded 30 years ago in Brazil — could use a clearly defined concept. Sure, Rock in Rio presented one weekend dedicated to rock (with headliners Metallica and No Doubt) and another to pop (with Taylor Swift and Bruno Mars). Beyond that old-fashioned sorting system, though, it was hard to detect what the festival was trying to tell you about music in 2015.
Other points of uncertainty include how to bring more shade to the stretch of sun-baked blacktop next to Circus Circus and how to boost food offerings to meet Las Vegas' high standards.
That said, organizers knew at least one thing for sure: Mars would close out the proceedings with a bang.
As fine a performer as any working in pop right now, the 29-year-old singer was a perfect choice for a festival as broadly conceived as this one, with a thousand-watt smile and a deep bag of eclectic hits almost impossible to dislike.
Mars' show Saturday stuck closely to the well-oiled production he brought to Staples Center two years ago, down to the medley of '90s R&B tunes he dropped into the middle of his song "Our First Time." (The set opened with a version of the drum solo Mars played during last year's Super Bowl halftime show.) Yet he and his expert band put so much charm and energy into the music that you hardly minded hearing it all again.
"Saturday night and we in the spot," Mars sang in "Uptown Funk," his recent No. 1 hit with Mark Ronson, and for the duration of his set, there was no better place in Vegas to be.
Using Rock in Rio not as a victory lap but as a launching pad, Swift was nearly as skillful Friday night in a headlining performance that doubled as the first U.S. date of her world tour behind her smash "1989" album.
When she released the record last year, this onetime teen-country phenom said "1989" finalized her long-threatened transition to pop, and here that evolution carried over to the stage, thanks to an eight-piece band happy to juice its sound with synthetic tones.
More than any sonic shift, though, what you really noticed was the change in Swift's attitude, from the wide-eyed wonder she used to project to the pleasure she's now clearly taking in her position as an A-plus-list celebrity.
In "Blank Space," she swung a golf club as she made fun of her reputation for playing romantic games, while "Style," with a dozen male dancers moving around her on roller-skate shoes, felt like a clever riff on Madonna's "Material Girl" video.
The show also featured video testimonials by some of Swift's famous friends — short clips in which Lena Dunham and Selena Gomez, among others, described the singer's brilliance and generosity. But the videos were merely belaboring the central point of her performance: The naïf has become a boss.
In fact, Swift was one of a few powerful women on the bill for Rock in Rio's second weekend, an encouraging development for a festival circuit on which male acts far outnumber female.
Performing back to back Friday on one of the festival's smaller stages — one that, like too many elements at Rock in Rio, bore the name of a cool-hunting corporate sponsor — Charli XCX and Tove Lo found sly, funny ways to rough up glossy synth-pop tunes about looking for a good time (and not being ashamed of it).
And Brazilian singer Ivete Sangalo, dressed to impress in a sparkly cat suit, roused the main-stage crowd with tautly constructed songs that she said expressed her love for her country.
Rock in Rio's lack of organizing principle didn't keep 172,000 people from showing up over both weekends, according to the festival. What they found were some individual artists who made strong arguments of their own — and some who didn't.
Joss Stone, the British soul singer, started out mellow but ended up sleepy in her set of reggae-inflected love songs. Something similar went for John Legend, who seemed to disappear into his super-smooth arrangements, even in renditions of Marvin Gaye's aggrieved "What's Going On" and "Glory," Legend's Oscar-winning anthem from "Selma."
Armed with throbbing electronic beats and trippy digital-nightmare visuals, the Australian dance outfit Empire of the Sun had no such trouble making an impact. And though there was something appealingly perverse about its harsh treatment of this sun-dazed crowd, the group's attack went on about 45 minutes too long.
Next time — assuming there is a next time — Rock in Rio should give those minutes to Mars. He'd know just what to do with them.