Last month, Miley Cyrus told MTV News about her plans for her 18th birthday, which she said would probably include "a fun party and then maybe ... a vacation with my family." On Friday (December 10), we finally saw footage of that party — or, at least a party — though Miley probably wishes we hadn't.

TMZ.com has posted a video clip of Cyrus smoking a bong — reportedly filled with salvia, a psychoactive (though, in her home state of California, technically legal) herb — and then collapsing in a fit of giggles while her friends egg her on ... and, somewhat inexplicably, Bush's "Come Down" blasts in the background.

"Having a little bit of a bad trip," Cyrus laughs in the video, moments after taking a hit. She then randomly switches topics, shouting (at something or someone off camera), "Is that Liam [Hemsworth]'s lookalike, or what the hell is that? Is that my boyfriend?"

She then spends roughly the next 90 seconds laughing uncontrollably while someone behind the camera asks her to "tell us your thoughts, girl, tell us what's on your mind!" and an unidentified man in the background totally houses a box of Frosted Flakes.

According to TMZ, the video was shot in Cyrus' Los Angeles-area home on November 28 — five days after her 18th birthday — and it was one of her friends who did the filming. The website quotes an anonymous source as saying that "someone stole or copied the video from that friend's camera."

At press time, a spokesperson for Cyrus had not responded to MTV News' request for comment on the video.