If Karen O had a whim to release a new wave of Jazzercise videos she would not need to look any farther than her own live show footage to have an instant hit on her hands. The Yeah Yeah Yeahs front woman had the crowd whipped up into a bouncing frenzy in Marymoor Park last night, proving that Seattle crowds can and will get down on a Monday.

Before the mighty YYYs came out, opening act Har Mar Superstar had some concert-goers questioning the identity of the mystery man. Google image results proved to be unsettling. But as the R&B shaker shimmied across the stage singing not-so-subtle songs like “Tall Boys” and “We Don’t Sleep” (he’s not talking about slumber parties) the crowd laughed out relief. His signature flare and strip tease won over even the parents who had taken their teenagers to a rock show in the park.

The army of devoted Yeah Yeah Yeah fans didn’t have to wait long before a bright yellow Karen O roared out with recent single “Mosquito” fed by Brian Chase’s fevered drumming. The gang worked a wide variety of its rock arsenal, varying from the sensually raw powered “Rich” from the Brooklyn band’s smash debut Fever To Tell to the hopelessly breathy “Skeletons” from It’s Blitz!. “Sacrilege” highlighted the new material as the revival took on a new life in the hands of guitarist Nick Zinner, whose riffs drove home the song with force.

Yet it was hard to say who was having more fun during the 90-minute set, Karen O or the audience. During “Cheated Hearts” the fearless leader worked her way along the front of the crowd having fifteen or so fans wail out “oo oos” into the microphone. She burst out with joy exclaiming, “I could reach out and touch you!” One guy yelled back, “You can touch me anywhere!” Even though “Zero” landed in the middle of the show the song received a sing-a-long that’s usually reserved for the encore.

Whether fans had been there since the beginning of the band’s decade-plus history or jumped in the last few years everyone left with satisfied grins plastered on their faces. And, yes, they still played “Maps.”