Later in the evening, she covered up her disco-ball-style nipple pasties with a black mesh shirt she said she stole "from a stripper."
Patrick Schwarzenegger, who said he'd been awake and working out at 5 a.m. that day, was her date.
That's pretty much the story right there. However, more details follow!
The "Bangerz" babe was photographed smoking weed onstage during both the rehearsal and the private show, where she performed covers of tunes by Led Zeppelin, the Beatles and Johnny Cash as well as an original number that, according to the Associated Press, she wrote after her friend's cat spoke to her in a dream.
Earlier in the day, during her sound check, Cyrus had subtly (everything is relative) hinted at the nighttime look that was to come, trotting around in a crop top with a white body and long pink sleeves -- and outlines of naked breasts in the anatomically appropriate spots.
After the show, she ditched the leotard-thong thing, put on denim hotpants and took on the world, or at least a nightclub, in her full nipple-pasty glory. By the time she slurred her way out to an awaiting car, as seen in a paparazzi video posted by the Daily Mail, she'd procured a black bra.
The Miami Beach incarnation of Art Basel opened Thursday and runs through Sunday.