French black metal mystics Deathspell Omega play things close to the vest.

They don't tour, their lineup is purely theoretical (no band photos, ever), and they don't do interviews.

They say everything they want to say through their music, which takes the aggression of black metal and marries it to the compositional complexity of '70s creepy-prog acts like Van der Graaf Generator and Univers Zero, the latter in particular.

This album is the culmination of a trilogy that began with 2004's Si Monumentum Requires, Circumspice (in Latin, "If you seek his monument, look around you") and continued on 2007's Fas -- Ite, Maledicti, in Ignum Aeternum (in Latin, "By divine law, go, you cursed, into the eternal fire"), the point of which is to seriously debate Christian theology -- God versus Satan -- from a base of deep textual knowledge.

These folks have not only read their Bibles, they've read years' worth of theological interpretation and argument, and while they mock Christianity, they do so from a perspective of thoroughly informed respect, ultimately seeming to reach the conclusion that to be human is to be satanic and that God demands that we renounce our innate nature.

None of this matters, of course, unless the music works as music.

If the sounds aren't interesting, the band might as well send out the lyric sheet as a pamphlet, to be read and debated.

And musically, this is Deathspell Omega's most conventional release since their early, pre-trilogy releases.

It's extremely aggressive; the guitars break into post-punk dissonances from time to time, but the female vocals and choral interludes that marked Si Monumentum are gone, as are the passages of creepy near-silence.

The rhythmic complexity and intricate compositions of the last two albums remain, but the music barrels ahead at all times, ten tracks of theological debate set to blasting riffs and punishing drums, with the vocals croaked in English, French, Latin, and maybe another language or two here and there.

Deathspell Omega are black metal's deep thinkers, and if this isn't their masterpiece (that would be one or the other of its predecessors), it's a superb cap to a major multi-part work of art.