In the 19th century, British philosopher Jeremy Bentham proposed a model for a new type of prison. This prison, named the "panopticon", was to be a large, cylindrical tower, with cells divided up like slices of a pie, thus enabling a large number of prisoners to be able to be observed by a single jailer. As time went by, Bentham refined his ideas, incorporating things like one-way mirrors and complex maze-like structures into his jail, so that the prisoners would not even know if they were being observed or not. Although a panopticon was never actually constructed, the ideas were refined after Bentham's death, and can be seen in today's widespread video surveillance and observation systems - which allow a single person to potentially observe a large number of people at the same time, without the knowledge of those being watched.

"Panopticon", the latest album from Isis, is not a British prison, but instead a heavy metal album that slowly burns and smoulders with energy, rather than releasing it with the quickflash speed that other heavy metal bands are wont to do. Isis records have always divided the listening public, and this one is no different; people will either love it to death for challenging the preconception that heavy metal has to be fast and brutal, or they'll have it for being dull, and slow to get to the point. Both viewpoints are legitimate where this band is concerned, their brand of ponderous grandeur is difficult to get into (probably deliberately so), but once it clicks, Isis fans can't seem to praise the band enough.

The best way to describe this music would be as a mixture of Slint, due to the awkward, deliberately uncomfortable nature of most of the songs, and Blood and Time, with their purposeful metal minimalism. Opening track So Did We features lumbering guitar riffs, thudding bass, and vocals growled with just the right amount of menace that they sound threatening, rather than cheesy. In the true fashion of this band, somewhere around the halfway mark, the song radically changes direction, this time with a reverberating bass line providing the muscle of the song, and crystal-clear guitar notes twisting around it. This is heavy metal, but not as the mullet-sporting guys down at your local bikie bar know it.

Wills Dissolve, about halfway through the album, is the most accessible song of the batch, sounding a little bit like Tool. The prog-sounding guitars come out, and the theme and melody rush around and around in circles until it acquires a critical mass of energy, releasing it all in a brutal crescendo. Backlit, on the other hand, starts out with a gentle introduction, before tornadoes of distorted sound punch their way through the melody, which are in turn replaced by sparse, clear guitar sounds that sound not unlike the calm after a destructive storm.

It's impossible to really say whether any given person will like "Panopticon", such is the nature of the sound here. Established Isis fans will probably enjoy this, and fans of bands like Tool and Mogwai might also enjoy the at times progressive and post-rock sounds that the band can produce. On the other hand, the music that this band makes is so radically different to what popular notions of heavy metal are, that many people will find it dull and pretentious. It's worth checking out, but borrow a copy from someone else before you actually throw down your money.