For more than a quarter century, Dream Theater have carried the torch for progressive metal, taking a fusion of styles that, for many years, applied only loosely to bands as diverse as Iron Maiden, Queensryche, Fates Warning and even Rush, and truly making it a “thing.”

Dream Theater was formed in Long Island, New York, in the mid 1980s, originally as Majesty, by a trio of Berklee College of Music students -- guitarist John Petrucci, bassist John Myung, and drummer Mike Portnoy – and a high school friend of Petrucci’s, Kevin Moore, on keyboards.

Over the next few years, the young band recorded a series of demos (released on cassette as The Majesty Demos) while perfecting their craft, working with several vocalists before hiring the much older Charlie Dominici to record their debut album, When Dream and Day Unite, for the independent Mechanic Records.

But Dominici lasted only four shows and the band eventually recruited a more suitable replacement in James LaBrie, signed a new deal with EastWest, and proceeded to take the metal world by storm with their watershed sophomore album Images and Words, actually scoring a hit with an edited version of its opening track “Pull Me Under.”

Dream Theater’s career effectively took off over the next few years, though you could say that the band accomplished this in spite of consistent meddling from their record label, always seeking another hit from subsequent albums Awake, the A Change of Seasons EP, and the unhappy compromise of Falling Into Infinity.

But with the stubbornly conceptual Metropolis Pt. 2: Scenes from a Memory, Dream Theater (now featuring keyboardist Derek Sherinian, later replaced by Jordan Rudess) dug in their heels and determined to follow their original art metal muse over ensuing releases like Six Degrees of Inner Turbulence, Train of Thought and Octavarium.

Come 2007’s Systematic Chaos (2007), the group began a new and fruitful relationship with the more metal-friendly Roadrunner Records, but after 2009’s Black Clouds and Silver Linings they had a real crisis on their hands when they fell out with founding drummer Portnoy, who had pursued a gig in Avenged Sevenfold and ultimately wasn't welcomed back to the band.

But Dream Theater quickly rebounded instead, adding drummer Mike Mangini for the aptly named A Dramatic Turn of Events, and showing no sign of slowing down over two more albums – a self-titled effort and 2016’s once again fully conceptual The Astonishing, and this pretty much brings us up to date on their story.

So click through the gallery above to see how we ranked Dream Theater’s albums from weakest to strongest.

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