Genesis: Trespass (1970)
This was the band's second release, but their first "real" album (their debut was really just a bunch of college-age songwriters thrown in the studio with their songs gussied up with strings, making it sound more like a Moody Blues or Bee Gees album, though I think the songs themselves are far better than word may have it). It's a little more undercooked, and less playful, than what would follow; and the band is not yet in its complete "classic" formation (Phil Collins and Steve Hackett would join for the follow-up, Nursery Cryme). But the pieces are all there -- the lengthy, epic tales that seem drawn from mythology, Gabriel's distinctively dramatic vocals, the complex keyboard and guitar interplay that draws from In The Court of the Crimson King and classical music.
And the songs are just great. The highlight is the sprawling "Stagnation," a gorgeous suite that stands as one of the less heralded yet definitive prog pieces; followed by the noisy and abrasive but unusually cathartic "The Knife," the one song from the album that would endure as an early concert staple after most of this was dropped from the set.
But you've also got album opener "Looking for Someone," a relatively unpolished but still dense and compelling piece that boldly announced an entirely different band than that heard on the debut; and the lovely opus "White Mountain," another winding narrative that made a brief appearance in the band's live set in the early Collins-helmed era but was unwisely dropped. And "Visions of Angels" is maybe a bit overwrought, but the piano passages are still gorgeous and the song works well as part of the larger whole.
Trespass may not be the best entry point into the Gabriel era (stick with Selling England) and is unlikely to convert anyone new to prog, but it's highly underrated.
Here's the Gabriel-era band playing the closing half of "The Knife":