Both Tool and Alice in Chains took part in the Lollapalooza tour in the summer of 1993. At various stops on the trek, late Alice in Chains singer Layne Staley would join Tool on stage. The team-up would occur during "Opiate," with Staley contributing vocals to the title track of the Maynard James Keenan-led act's 1992 EP.

Thankfully, at least one camera-wielding concertgoer captured the collaboration on tape. Take a look, toward the bottom of this post, at the video of Staley and Tool rocking the song in Kaneohe, Hawaii. It was part of the Big Mele Festival on Aug. 15, 1993, where Tool were playing after Lollapalooza wrapped up.

That year, the Big Mele also hosted Fishbone, Stone Temple Pilots, Violent Femmes and Primus. Alice in Chains weren't on the bill, so it's unclear why Staley was on hand to reprise his "Opiate" duet with Keenan. Still, the footage makes it clear that's what happened between "Sweat" and "Flood" in Tool's set.

In the video, the barechested Tool members give it their all as the Alice in Chains icon — situated beside guitarist Adam Jones — joins Keenan in the song's refrain. The attendees certainly seem to be feeling it. Amid a picturesque oceanside backdrop, it'd certainly be hard not to rock out to such a lively rock partnership.

At the time, Tool had released Undertow just a few months prior. Alice in Chains issued Dirt the previous fall, and they would go on to unleash their self-titled album in 1995. Sadly, Staley died from a drug overdose in 2002, causing Alice in Chains to step out of the spotlight for a time until their 2005 reunion.

Tool Featuring Layne Staley, "Opiate" (Live in Hawaii) - Aug. 15, 1993

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