San Francisco-based post-rock five-piece Lotus Thief are hard to sum up in a few words, taking influences from all over the underground metal scene from black to doom as well as more post-metallic genres. Featuring members of oddball plantophiles The Botanist and self-describing themselves as "text metal", they draw inspirations for their albums from ancient texts such as the Egyptian Book of the Dead, and create intensely atmospheric concept albums accordingly. Oresteia is the group's third full-length, and is based upon The House of Atreus written by ancient Greek playwright Aeschylus, and the result is a dreamy, atmospheric album driven by a stirring blend of vocals (mostly female clean and harsh male) that weaves in and out of metal between bursts of ambience taking the form of interludes such as Banishment. There's an obvious theatricality to this, not least on eight-minuter opener Agamemnon which approaches a triumphant grandiosity at points as it rises and falls with the title character's fate, and it does help to sit and read the lyrics as they are sung; a live performance of this could be fascinating, depending on how much the band veer away from a traditional metal show.

Yet even just in audio, Oresteia is still a compelling experience. Libation Bearers takes on a more strident heaviness, some growled and screamed vocals atop the post-metal riffs reminding you of the band's blackened past, contrasting well with the album's catchiest chorus. The female vocals are always rather beautiful but at their best on The Furies, leading the first two minutes of the song before some languid yet hurried riffing and a more technical, almost blackened gallop takes hold, dying into electronic-backed ambience - the overall vibe something like a darker Dead Can Dance. Sister in Silence dips outright into black metal in sections, the gnarliest song on a not particularly gnarly album. And the ambient interludes are all worthy of your ears too, especially the longer pieces like the three-minute-plus Woe or outro The Kindly Ones, which uses the vocals in an especially dreamlike way. An odd but not unlikeable album, Oresteia is likely to be too post-rock for metal fans and too close to metal for post-rock fans, but it mixes the two worlds well and is wonderfully-written. Not for everyone, perhaps, but fans of Ancient Greek tragedies and experimental black metal will find much to like! Listen to (and buy) this from Bandcamp.