MGMT have never been an easy band to peg down. Even back when their super-catchy debut album, the psych-pop extravaganza 'Oracular Spectacular,' dropped in 2008, the New York-based outfit seemed nothing if not particularly uninterested in appeasing its rapidly growing fan base.

A half-dozen years and a couple puzzling albums later, and little has changed -- as evidenced by their bizarre appearance on the 'The Late Show With David Letterman' last summer to perform 'Your Life Is a Lie,' a track off their latest, self-titled record.

MGMT's first brushes with the spotlight offered a taste of things to come. When they turned up for their network television debut performance in 2008 (also on 'Letterman') to rock out their first single, 'Time to Pretend,' they were teased a bit for their odd fashion choice -- dressing up in capes that made them look like Dungeons and Dragons outcasts.

And when their big, synthy uber-hit 'Kids' was starting to pick up steam later that year, they seemed perfectly content waiting months before finally making an official video for the cut while a low-budget, fan-made clip racked up millions of views on YouTube.

Things only got more bizarre from there. 'Oracular Spectacular' made MGMT bona fide rock stars, but when it came time for the disc's follow-up, 2010's 'Congratulations,' principals Benjamin Goldwasser and Andrew VanWyngarden blatantly ignored the infectious pop stylings that put them on the map in favor of a more challenging, prog-rock sound -- and the reviews were mixed, to be generous.

"It's us trying to deal with all the craziness that's been going on since our last album took off," VanWyngarden told the San Francisco Examiner at the time. "Sometimes it just doesn't feel natural."

Perhaps what felt more natural to MGMT was the head-scratcher of a performance they put on when they returned to 'Letterman' last August to run through 'Your Life Is a Lie.' We'd give you a blow-by-blow run-down of the action, but it's probably best to say that it involved Wyngarden banging on a oversized cowbell while his bandmates tried their best to look like they'd rather be anywhere else on Earth and leave it at that.

Really, this one should be seen to be believed. Check it out above.

That more recent 'Letterman' gig was widely panned by the blogosphere, the Twitterverse and pretty much anybody else who cared to share an opinion, but we think it'd be too easy to simply say they blew the show off. Despite the nonchalant attitude that they often put out, it seems pretty obvious that MGMT actually do care -- they just care to do things their own way. Call it "MGMT Being MGMT."

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