With 2006's Operation: Mindcrime II (Rhino Entertainment), Queensrÿche ask the question: How do you follow brilliance? After releasing what is widely considered one of the finest heavy metal albums of all time (1988's Operation: Mindcrime), the temptation to rest on their laurels must have been overwhelming. But there are more stories to be told, and as Nikki the drug addict and convicted murderer is released from prison, he's got one thing on his mind: "I'll kill the bastard."

But much like revenge itself, Queensrÿche's continuation of their masterpiece isn't a solid affair. Some of the tracks wheeze and flutter along as middle-of-the-road rock songs ("Hostage", "Speed of Light"), while others cruise ahead, whether rocking out (the excellent "Signs Say Go") or casting a melancholy, introspective eye inwards ("If I Could Change It All" and "A Junkie's Blues"). Operation: Mindcrime II works brilliantly as a concept, but the lack of consistency from song to song holds it back.

Ronnie James Dio and Pamela Moore provide guest vocals, as Dr. X and the ghost of Mary, respectively. You can never go wrong with Dio, and to hear him and Queensrÿche vocalist Geoff Tate trading vocals off each other in "The Chase" is a treat. Moore has always been one of the most dynamic female voices in rock music, and hearing Mary's voice from beyond the grave make her songs leap off the CD and into your bloodstream.

Unfortunately, while the original Mindcrime did this on a regular basis, it happens only intermittently with the sequel. Most of the first half of the album simply wobbles along ("I'm American" is a very pleasant exception), with the pieces only really coming together in the second half. While there are unquestionably good songs on Mindcrime II, there are none of the classics that the first album gave us (although "If I Could Change It All" does come across as a decent successor to "Suite Sister Mary", and "A Junkie's Blues" hints at "Eyes Of A Stranger").

The question will be asked, should Operation: Mindcrime have been continued? The album ended masterfully in 1988, with Nikki's memories returning and his desire for revenge taking form. It was a perfect cliffhanger to a perfect album. Queensrÿche should get credit for not taking the easy way out, and doing something a lot of bands would balk at doing. If anything, Operation: Mindcrime II will remind us of how high Queensrÿche set the bar in 1988, and that can't be a bad thing.