On Abyss, Chelsea Wolfe brings the heaviness in her music to the fore in a way that's more natural, and more compelling, than merely "going metal." Given the darkness and drama present even on her unplugged album Unknown Rooms -- as well as tours and collaborations with artists such as Russian Circles -- it was inevitable that she'd embrace her metal leanings more fully, but Abyss exceeds expectations. As always, she enlists old and new collaborators to help her bring these songs to their full, heavy glory. Along with her longtime bandmates Ben Chisholm and Dylan Fujioka, this time the players include Russian Circles' Mike Sullivan and True Widow's D.H. Phillips, and their contributions make each of the album's meditations on love and loss feel like an event. "Iron Moon" -- which was inspired by the poetry of a suicidal Chinese factory worker -- alone boasts guitars that shift from a viper's nest to folky delicacy to obliterating blasts. This heaviness is a perfect contrast to Wolfe's vocals, which sound clearer, purer and in the case of "Dragged Out," where they hover like tortured souls over a pit of lower-than-low riffs, eerier than ever. However, Wolfe is too much of an artist to just rely on metal tropes, and many of Abyss' best songs defy easy classification. She pairs tightly wound industrial beats and swooning vocals with doom metal guitars on "Carrion Flowers" for an effect that's alternately slinky and head-banging; "After the Fall" is even more eclectic, combining deconstructed electronics and seething riffs in an unsettling and captivating fashion. Meanwhile, the stand-out "Survive" focuses on her vocals -- which have an R&B cool to them here -- and thundering drums for its formidable, desperate sensuality. Wolfe also finds time to honor the ethereal side of her music, and respites such as the string-driven "Grey Days" and "Crazy Love," and the gorgeous "Maw" are gentler but no less compelling than the album's climaxes. More than ever, Abyss proves that she knows when to unleash her full fury and when to rein it in, and the results are stunning.