When Long Island’s Blue Oyster Cult released Secret Treaties in April 1974, their future standing as bona fide hard rock legends was anything but guaranteed. But it certainly helped that the band’s third album (and final installment in their so-called “black and white” triptych) happened to be their best effort yet -- by far.

Their sophomore outing, Tyranny and Mutation, had undoubtedly paid off on some of the tenuous promises made by the group’s eponymous debut. But its inconsistent songwriting and sheer aesthetic schizophrenia clearly revealed the band’s lingering directional uncertainty.

Eric Bloom, Donald Roeser, Allen Lanier, Joe and Albert Bouchard had clearly still been searching for their identity, and most people would agree that Secret Treaties is where they truly found it. Their songwriting abilities had improved enough to let them carry on exploring a relatively varied range of musical styles and lyrical themes within a mostly heavy rock framework.

And they had some talented friends helping them out, too. Punk queen-in-waiting Patti Smith penned the words for the new LP’s irresistible opener, "Career of Evil," while another literary pal, pioneering rock critic Richard Meltzer, provided lyrics for the unapologetic "Cagey Cretins" and the downright creepy "Harvester of Eyes." (Both lyricists had already lent some help on Tyranny and Mutation).

Elsewhere, band manager Sandy Pearlman handled the bulk of B.O.C’s cryptic wordplay, but it was the aforementioned quintet of musicians who crafted the all-important, increasingly accomplished songs supporting them — including future concert favorites like the hard driving "Dominance and Submission" and the astonishingly finessed, piano-led "Astronomy."

Secret Treaties was also the band's first filler-free album, thanks to sturdy album tracks like Bloom’s ominous "Subhuman," the beefed-up, turbo-charged ’50s rock of "ME 262" and the dynamic and dramatic "Flaming Telepaths," featuring particularly stunning leads from six-string hero Buck Dharma.

All of which catapulted Secret Treaties to a gold certification by the RIAA and elevated Blue Oyster Cult to arena headliners for the year-long touring that soon followed — later commemorated by the first of many live albums, On Your Feet or on Your Knees.

By the time the band began working on their fourth studio album, Agents of Fortune, in late 1975, they’d struck a secret treaty with hard rock fans everywhere and established a momentum that would keep them roaring right through the '70s.

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