Imagine relaxing in a dive in Phnom Penh, Cambodia, circa 1965, brushing elbows with off-duty soldiers, local gangsters and Western diplomats as a hip band plays a mix of rock, soul, jazz, surf music, traditional Cambodian tunes and Henry Mancini and John Barry spy-movie motifs. That was an easy fantasy to indulge Wednesday night at the Black Cat, where Dengue Fever played an energetic set for fans who were mostly too young to remember what happened in Southeast Asia in the ’60s and ’70s. Perhaps there was some regret in the Khmer lyrics warbled by Cambodian-born lead singer Chhom Nimol, but the band’s music and manner were overwhelmingly upbeat.

Wearing a backless gold dress, Nimol didn’t disappear during the L.A. sextet’s 80-minute set. But the petite singer had more competition in concert than she does on the group’s recordings. The towering Senon Gaius Williams was all over the stage, playing the role of cheerleader as much as bassist. Sax, trumpet and flute man David Ralicke was equally exuberant, and guitarist Zac Holtzman attracted attention with his verve but also with a beard worthy of an Orthodox rabbi and a two-necked instrument, the mastodon, which combines an electric guitar with a traditional Cambodian lute, the chapei dong veng. (Used briefly, the hybrid was more important visually than musically.)

Williams did take a political stand of sorts, announcing the group’s support for Wildlife Alliance, which works to save endangered Asian animals. But the band’s English-language songs were mostly playful riffs on troubled romance, sometimes sung as duets between Nimol and Holtzman. “Cement Slippers” was a he-says/she-says account of an incompatible couple, while “Tiger Phone Card” was about lovers separated by more than distance.

Although the crowd-pleasing performance couldn’t be termed “down tempo,” the music sometimes recalled that of another group with a thing for 007-movie soundtrack composer John Barry: Portishead. Both outfits conjure a lost musical golden age that never quite happened. But where Portishead cultivated distance, Dengue Fever vigorously engaged the audience. Nimol flipped her microphone toward the fans for singalongs as the other musicians bounced around the stage, as if urging everyone to hurry into the band’s time-and-space machine. C’mon, next round in Phnom Penh!

Jenkins is a freelance writer.