Heroin is a hell of a drug. Singer Layne Staley was in the midst of a debilitating addiction to the substance while recording Alice in Chains’s second record, making this metal/grunge hybrid a harrowing look into an embattled mind. Not an easy listen for sure, but Jerry Cantrell’s filth-covered Iommi riffs make everything go down easily. The best songs are the big ones: “Them Bones,” “Rooster,” “Would?,” “Angry Chair.” Staley’s voice contains multitudes and he fills each tune with his pain. Less than a decade later he’d be gone, a victim to his vices, but he left an indelible stain on the rock landscape here.