Friday night at Hiro Ballroom, the elusive Swedish duo of Magnus Zingmark and Oscar Simonsson, also known as Koop, roared back to New York to treat a packed house their unique brand of kicky and atmospheric vintage grooves. A mass of dusky-haired neo-beatniks and smartly-dressed neo-jazz enthusiasts swayed, bibbity-bopped and darn near jitterbugged to their stunning repertoire of old and new songs during their first US performance in over five years.

The duo, clad in mod all-black ensembles, commanded the stage from the center of a six- piece band decked out in baggy-pants, suspenders and other big band finery. They opened the set as the buttery-voiced vocalist cooed, "Koop Island Blues," the first song on their latest album, Koop Islands. Next, the band segued into some early material where the xylophonist riled the crowd with a blithe percussion solo and then transitioned into a sultry salsa-tinged bridge.

The momentum continued with a souped-up rendition of the jocular, "Come To Me," featuring a rollicking drum solo and a surprisingly nimble trombone solo evoking the glittery jazz era. The night continued as the vocalists changed shifts and a male singer led the band with his jazz guitar on the sensual and understated, "Let's Elope." Then song seamlessly melted into the playful scat number, "The Moonbounce."

After the dreamy "Strange Love" they drew pouty boos from the crowd as they proclaimed the jaunty "I See A Different You," the last song of the night. Lucky for the kids, Koop was just joshin' and turned out not one but two encores, packed with a guttural double bass solo, an enlivened reworking of the brooding trip-hop track "In A Heartbeat." They rounded out the two-hour set with a gleeful reprise of "Come To Me."

It was a truly entertaining night where skilled musicians adept in several genres took center stage. Even though the repertoire included mostly jazzy rhythms inspired by the 1930s and 1940s, Koop was thoroughly modern in their ability to create a dynamic performance that infused their jazz and electronica styles. And for a group that hasn't touched down on US shores in half a decade, it was a triumphant and very welcome return.

Photos from the show | "Koop Island Blues" Video