Foster the People's concert at the Wiltern on Saturday was akin to their rise to superstardom: explosive. They jumped from total obscurity to chart-topping fame and incessant radio play on virtually every station under the sun in a matter of weeks. But with that kind of just-add-water celebrity comes a price: while Mark Foster and his crew were giving a revved up performance worthy of the Coachella main stage, their audience was asleep at the wheel. 

It was clear long before FTP took the stage that they'd be dishing out more than they'd get back in return. During their opening set, Madeline Follin of the dreamy mop-headed indie duo Cults actually shouted at the dormant crowd, "Wake up!" Evidently, the vast majority of concert-goers weren't there to see either Cults or the band that played before them, Reptar.

That didn't stop the Athens, GA-native band from killing it at their first show in Los Angeles. Reptar took the stage like a newly formed band playing a gig at a college party packed with their buddies. Shoes off, hair amuck, brews in hand and beaming smiles, they had that young and raw energy of a band on the rise. It's that bittersweet sentiment that makes you simultaneously pray they'll get the attention they deserve, but also hope that they can stay this organically awesome forever. 

Reptar's got a Passion Pit meets The Cure kind of sound, infusing eighties pop with a modern electronic spin. They dance about like little boys pretending to be tribal warriors. Never before has their been a greater justification for the call for "More Cowbell!" than on their tune "Sebastian." "Stuck in my Id," off their August EP Oblangle Fizz, Y'all! seals the deal; you won't want to miss them the next time they roll into town.

Cults followed, kicking off their set with "Abducted," which Pitchfork dubbed a Best New Track back in April. Cults can be intimidatingly cool, but their sound is infectious. Follin and her creative partner Brian Oblivion, along with three more live members with, of course, equally long, shiny black tresses have a new wave Motown vibe. Their recordings are packed with xylophone twinkles and whimsy, but live, their sound is a whole lot grittier. The naïveté one might expect from the (ironically) Sasha Grey lookalike is nonexistent; she was surprisingly more Janis Joplin than Best Coast. 

Behind the band, old black and white movies were projected, completing the nostalgia that filled the vintage art deco theatre. The scene made you wish your life was a series of Super 8 movie montages as you swayed to the chimerical sounds. They delivered a generous 10 tracks, but it was all too apparent that most of the audience was oblivious, clinking Heinekens and razzing their bros instead of appreciating the wonder that was Cults.

Then, the band that apparently everyone had exclusively been waiting for, Foster the People. It was the first of two shows they'd be playing at the Wiltern (the second of which was on Tuesday). Their setlist was predictable, but their performance was not. They played all 11 tracks off their debut album, Torches. Nothing more and nothing less. 

L.A.-native FTP opened their set with "Houdini," a single that played on season premieres of, oddly enough, both Entourage and Gossip Girl. Tonight was obviously about two things, and two things only: bass drums, and Foster's dancing feet. In Southern California style, the ground shook with Mark Pontius' pulsing drum beats. And if those weren't enough, the other band members gleefully passed drumsticks around like a Humboldt County joint, taking turns slamming down on other drums scattered across the stage.

Meanwhile, a boisterous Foster bounced around from corner to corner like a ping pong ball.  The Wiltern always manages to put on light shows that are as memorable as the acts they spotlight, and tonight was no exception. Colorful strobing turned the band members into spastic silhouettes as they danced to the ferociously rhythmic "Miss You" and "Life on the Nickel."

Much of the audience seemed to be hearing these tunes for the very first time, but that didn't stop them from following suit. Mother-daughter pairs bumped hips while pairs of a different kind bumped uglies on the dance floor. The scene was better suited to a Rihanna concert.  

Before whiplash could afflict anyone in the theatre, Foster slowed it down for "I Would Do Anything for You," taking a mic stand at center stage. After, he took the opportunity to plug their Do Good Tour.  The band partnered up with the Do Good Bus, a literal tour bus that is following them around the country during their North American Tour. In each city the band stops in, the bus fills up with local do-gooders. Those lucky few are wined and dined while being driven to a surprise local service event. The question is, who gets more out of this project, the charities or the winos?

Foster waxed on for a moment about how lucky the band feels to have the chance to be artists in a city as vibrant as L.A. A little hometown lovin' can't hurt; everyone's energy was dialed up to 11 on "Broken Jaw" and "Waste." Fittingly, it seemed like the frontman's jaw might have fallen off as he howled the lyrics and shuffled about.  Foster the People's sound is far more textured live, and in a way, far less alternative. It was a genuine rock concert. 

That is, until "Call It What You Want," which might sooner be likened to an arrangement conducted by Gustavo Dudamel.  The band emphasized each part of the song, like movements of a concerto. It was a dynamic rollercoaster, and the acoustics at the Wiltern framed it perfectly, with the echoing voices on this tune seemingly coming from 360 degrees around.

"Don't Stop (Color on the Walls)" has the potential to be one of those beachy, California classics. Apropos that energy, the stage turned a swirly blue and green tie dye of fog and light, followed by purple flashes punctuating the chorus' upbeats. The scene took you over. It was hard to think of anything other than what was going on right before your eyes; the combination was almost synesthetic. It was too perfect, so of course, the sound had to cut out. But even Murphy's Law couldn't get FTP down.

"Helena Beat" was the last song in the set; the end had come much too soon. With a deficit of conscientious hipsters to (relatively speaking) patiently await the encore, sweaty pseudo-fans stomped their feet rowdily until they reemerged. FTP's penultimate tune, "Warrant," sounded more like the recorded track than any other song that night. Yellow and purple lights flickered, and I couldn't help but think that some bro tank-clad folks in the audience might have thought it was a bout of Laker pride. 

And now, what you've all been waiting for: "Pumped Up Kicks." This summer anthem was played ad nauseam by everyone from NPR to Ryan Seacrest, and their respective audiences came in droves to botch these lyrics in one hell of a chaotic chorus.  

"Hip moms" dropped their granny panties over what Hipster Runoff dubs the pinnacle of "bubble gum indie." As Foster said in an interview with Billboard, "At our shows [there are hipsters, and then] there are adults -- like moms with their daughters; moms who are way more into it than their daughters," he said. "We played a show in Minneapolis and there was a 60-year-old woman just going crazy."

"Pumped Up Kicks" is 2011's version of MGMT's "Kids;" the oblivious masses bob their heads to the synth-pop, blissfully ignorant of the brutal words they're calling out. It's the story of an unhinged kid driven to random spells of violence, so naturally, a wild display of rainbow lights filled the stage.

It's far from their best tune, actually, but the audience was enraptured all the same. FTP topped it off with a disco interlude, then finally a dubstep-infused remix. Reptar joined them on stage to add even more percussion and flailing limbs. 

They were definitely having a blast, and so were we, though I don't think anyone was particularly heartbroken to part ways. There was a kind of disconnect between them and the audience. And while there's something to be said for being able to rock out that hard fueled only by their own passion, that reciprocity is integral to any concert experience. But this is what seems to happen when you've sold out before ever even being in. In "Call It What You Want," Foster sings, "Now what's your style and who do you listen to?" Something tells me that looking out at Saturday night's crowd, he would just as soon leave that question unanswered. 

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