No matter what you think of Norwegian black metal titans Dimmu Borgir, this much is true: they do not leave any ideas in the tank. Dimmu’s brand of theatrical black metal throws not just the kitchen sink at the listener, but the kitchen, the parlor and probably the garage. Blast beats, interlocking vocals between Shagrath and Vortex, Gregorian chants and spooky keyboards are just part of the operatic sweep of Dimmu’s sound. This isn’t just heavy metal, it’s Rosemary’s Baby set to music.

Lots of black metal fans yelled “sellout” as Dimmu integrated orchestras and went away from the lo-fi production style of contemporaries like Mayhem. But the thing is, Dimmu has done something that most would probably have thought impossible: they have proven that black metal can not only sound great, but it can also be a commercially viable art form. Just witness the high sales for the band’s 2003 album Death Cult Armageddon and the strong opening week sales for their new one, In Sorte Diaboli. Fans need not fret, the boys from Dimmu won’t be showing up on TRL anytime soon, but they have opened the doors for other bands to expand the horizons of black metal. Dimmu didn’t sell out; they just got too big for the genre’s limited parameters.

Dimmu’s new album is another bold new step for the band, into the murky waters of the concept album. In Sorte Diaboli is the story of a medieval priest who is tempted by Satan and embraces his dark side. As far as concepts go, it’s nothing groundbreaking; in fact, from a group of avowed Satanists it’s damn near mailed in it’s so predictable. The band sees the concept as some sort of operatic tale, but the storyline is fairly off-the-shelf.

If the story of In Sorte Diaboli is a five, then the music contained within is a solid nine. The first thing you notice about the music is that this is one of the loudest bands you will ever hear. The production work is topnotch; the band (especially drummer Hellhammer) is in peak form and Shagrath’s vocals convincingly play the role of the devil, while Vortex plays the role of the Greek chorus. “The Serpentine Offering” kicks the album off nicely, and both “The Chosen Legacy” and “The Sinister Awakening” provide plenty of ass-kicking, headbanging metal. “The Fundamental Alienation” is about as catchy a black metal song as you can find but still maintains the heaviness and grand scale of the rest of the record.

Dimmu leaves the ending of the record open-ended, creating the possibility of a sequel. They say sequels are never as good as the originals and the story here isn’t all that great anyway. But Dimmu leaves you curious to see what kind of deranged direction they are going to take black metal in next.