While the speed-freak adrenaline heaviness and shrouded occult mystery of Tyranny and Mutation is the watermark for Blue Oyster Cult's creative invention, it is Secret Treaties that is widely and critically regarded as the band's classic. Issued in 1974, Secret Treaties is the purest distillation of all of BOC's strengths. Here the songs are expansive, and lush in their textures. The flamboyance is all here, and so are the overdriven guitar riffs provided by Buck Dharma and Eric Bloom. But there is something else, texturally, that moves these songs out from the blackness and into the shadows. It offers BOC a new depth and breadth. While elements of psychedelia have always been a part of the band's sound, it was always enfolded in proto-metal heaviness and biker boogie. Here, BOC created their own brand of heavy psychedelic noir to diversify their considerably aggressive attack. It's a breathless rock monolith that is all dark delight and sinister pleasure. While BOC went on to well-deserved commercial success with Agents of Fortune an album later, the freaky inspiration that was offered on their debut, and brought to shine like a black jewel on Tyranny and Mutation, was fully articulated as visionary on Secret Treaties.