The now 40-year-old 'Foxtrot' isn't the greatest Genesis album, but it's the legendary prog-rock outfit's first great album. Building on the fragmented promise of 1970's pastoral 'Trespass' and 1971's sweeping-but-sonically-muddled 'Nursery Cryme,' the players (vocalist Peter Gabriel, keyboardist Tony Banks, bassist Mike Rutherford, guitarist Steve Hackett, drummer Phil Collins) and their individual personalities finally cohered into lasting songs, instead of just head-spinning riffs and soundscapes.

'Foxtrot' was also the first Genesis album that sounded as epic as the ideas, utilizing the skills of producer David Hitchcock and engineer John Burns. From the opening mystic mellotron chords on 'Watcher of the Skies' to the final full-band swirl on the 23-minute powerhouse 'Supper's Ready,' every instrument pummels with clarity and power.

But 'Foxtrot' is ultimately more than just great instrumental performances (though there are more than plenty of those). Though Rutherford has expressed his distaste for the track's busy attack in hindsight, 'Watcher of the Skies' features one of their tightest full-band arrangements, with Rutherford and Collins banging out a mind-numbing rhythmic pattern underneath Gabriel's powerful vocal. 'Get 'Em Out By Friday' is home to one of Gabriel's most clever (and linear) lyrics, and the arrangement is one of the band's most visceral and dynamic, moving from dense organ-bass-drums clatter to reflective 12-string passages. Hackett's solo acoustic piece 'Horizons' (based on a prelude from a Bach cello suite) is among the guitarist's most haunting moments, opening the second side with a soothing calm before the frenetic chaos of 'Supper's Ready.'

"I think (with) 'Foxtrot,' we were gaining confidence,' Gabriel reflected in an interview for the album's 2007 reissue. "I think we were confident in a way we hadn't been before. So that gave us the mental platform on which to build something like 'Supper's Ready,' which is still one of the things I like best, looking backwards."

Gabriel's not alone with that opinion: Many fans still consider the loopy, seven-part 'Supper's Ready' the band's crowning achievement, regardless of era or album. While Genesis would go on to hone and refine these ideas even further on their following masterpieces 'Selling England By the Pound' and 'The Lamb Lies Down on Broadway,' this track does indeed represent an early artistic peak, blending Gabriel's dark, Biblical-inspired lyrics with music that morphs from 12-string balladry (the opening 'Lover's Leap' section) to straight-up goofiness (the crawling 'Willow Farm' section) to heroic prog thunder ('Apocalypse in 9/8').

'Foxtrot,' though far from a 'hit,' was their first album to break the UK charts, landing at #12. It's a telling statistic: Before, Genesis had been a cult band; now the outside world was catching on. From here on out, they'd be impossible to ignore.

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