Pirate, I share Frod's opinion that Secret Treaties is BOC's finest album, but you really can't go wrong with any of the first three--Blue Oyster Cult, Tyranny and Mutation, or Secret Treaties. Agents Of Fortune is fairly decent, but much more polished than the other stuff, and it was the one that yeilded "Reaper". Worth having, as are two of their live albums, Some Enchanted Evening (Coolest. Cover. Ever.) and On Your Feet Or On Your Knees. My favorite of their later work is Cultosaurus Erectus.