A Perfect Circle, featuring Tool's Maynard James Keenan on vocals, snuck covers of John Lennon's 'Imagine' and Led Zeppelin's 'When the Levee Breaks' into their set at Lollapalooza in Chicago over the weekend.

Of course, the band APC-ified the songs, adding ominous beats, and in the case of 'Imagine' in particular, making an otherwise positive and uplifting song about peace sound tense and dramatic, thanks to the way this artful hard rock band manipulated the tone. Only APC could take a song with such a defined message, then make it sound so dark and droning, not to mention more than a little foreboding.

Both performances were perfect examples of cover songs where the artist takes charge and completely bends the tune to their specifications, style and genre, rather than switching up their personal style to conform to the original.

Who knew that 'Levee' could work even after the huge echoing stop of John Bonham's drums are replaced by a moody bass line and a minimalist beat? Or that a song as simple yet stunning as 'Imagine' could be full of such tension and release and sonic drama? Oh, right, MJK is involved, and he specializes in dark, creepy, beautiful rock and not even a John Lennon signature song is safe from the singer having his way with it.

It's always a testament to solid, quality songwriting when a song is malleable enough to fit multiple genres and styles, and on this night A Perfect Circle were smart enough to choose two such compositions to interpret in such unique ways. Would Lennon and Zeppelin be proud? Yeah, we think so.

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