THE WHO Join together with the band. RICK DIAMOND

I LOVE THE WHO dearly, and I have mixed feelings about seeing them perform in the year 2016. They probably do, too. This is the band that famously sang "Hope I die before I get old." And this is the band in which two of the founding members did exactly that, more or less: Not-old-at-all drummer Keith Moon died back in 1978, and only-a-little-bit-old bassist John Entwistle died in 2002. Both incidents were drug-related, the result of these musicians being unable to give up their rock-star excesses. That leaves us with curly-haired singer Roger Daltrey and windmill-armed guitarist/songwriter Pete Townshend to carry the Who's weighty time capsule into the present day, a freighted catalog that's filled with Townshend's songs about the simultaneous rage and optimism that accompanies adolescence and young adulthood. It's a tricky task for a pair of septuagenarians.

This particular outing marks the band's ostensible 50th anniversary and follows the release of a compilation called The Who Hits 50!, but the length of the tour—and a delay due to Daltrey contracting viral meningitis that necessitated the rescheduling of the Portland show from September 2015—means the numbers are being fudged a bit.

Daltrey, Townshend, Entwistle, and Moon became the Who in 1964, with a brief sidetrack under the name the High Numbers. They unabashedly courted London's mod scene as their fanbase, despite none of the members actually being mods. (Most of the Beach Boys didn't surf, either.) Playing speed-addled versions of Motown and Stax tunes for frustrated youths, the group attracted two would-be managers: Kit Lambert, the homosexual son of a famous classical composer, and Chris Stamp, brother to handsome English actor Terence. These two had their own chips on their shoulders, and they turned the band's careering, chaotic sound toward London's fledgling pop-art scene. At one gig, Townshend accidentally broke the neck of his guitar, then proceeded to deliberately smash the rest of it to bits. It became the band's trademark.

Those early Who records may very well be their best. "I Can't Explain" was a perfect debut single, grafting the Kinks' snarled guitar sound onto a seemingly bubblegum number about sexual confusion and frustration. And 1965's "My Generation" is nothing short of a cliché nowadays, but in conservative post-war Britain it must have been an outright shock: a blistering slice of sputtering outrage with a violent bass solo, ear-splitting shards of guitar, a beat that sounded like the drummer and his kit had been pushed down the stairs, and a stuttering singer that suggested mental instability, threatening to shout words not fit for radio.

It turned out that Townshend, under the careful encouragement of Lambert, had the makings of a remarkable songwriter. The big-nosed, awkward child of a hip musician and a beautiful singer, Townshend possessed all the ingredients to create a new rock-music vernacular. Like many young adults, he experienced rage and inadequacy, but Townshend was also articulate, art-bent, and insatiably curious. He was uncommonly self-aware about his approach to pop songwriting, too, and he sought to implant the Who's rebellious, excitable fans as characters in his songs. Townshend's lyrics weren't necessarily meant to represent himself, or Daltrey—this was you singing about alienation and the desperate search for identity in "Substitute." This was you recognizing a moment of carefree, sentimental joy amid the turbulence of youth in "The Kids Are Alright," even as Townshend offers a gentle reminder that this good time, like all good times, will pass.

Those early triumphs gave way to an awkward growing period of novelty songs and insouciant humor. When it worked, as on 1966's suite "A Quick One, While He's Away," or on 1967's jingle-laden pop-art masterpiece The Who Sell Out, it worked marvelously. When it didn't, as on the 1968 flop single "Dogs," it didn't. The Who wasn't quite sure what kind of band it wanted to be, and to make matters worse, its individual members didn't especially like each other very much. Daltrey, the band's leader from the early days, was nearly kicked out of his own group after he beat up Moon one too many times. And Moon, younger than the other members, was an energetic and inventive drummer onstage but an unreliable rascal offstage—popping pills, drinking excessively, and leaving no hotel room undestroyed in his wake. Moon was the Who's mascot even as he became the thorn in their side.

However, the band persevered and gelled, finding a massive audience with 1969's double album Tommy, a rock opera that finally matched the scope of Townshend's enormous ambition. While the countless re-stagings, orchestral interpretations, and Broadway musical and film versions have somewhat overinflated Tommy's standing, the original document remains a relatively intimate delight: four tight album sides of British rock 'n' roll that sound much more stripped-down than you probably remember. And when the Who performed it live, Tommy turned transcendent; look to disc two of the Live at Leeds CD reissue for a turbulent, jaw-dropping rendition of the rock opera that's a veritable missile of sound.

That 1970 live album was proof that the Who had perhaps become that fabled thing of myth: the best live band in the world. On it, all four musicians are virtuosos—in particular Entwistle, whose twanging bass guitar grunts out independent melodies all its own, providing distinct counterpart to Daltrey's muscly voice. As the '60s idealism gave way to '70s excess, rock bands were expected to be larger than life, and the Who did their best to meet expectations, making music designed to fill the arenas, stadiums, and muddy festival fields that were now their domain.

But unlike the good-time party boogie of contemporaries like Grand Funk Railroad or the sexual depravity enunciated by fellow Englishmen Led Zeppelin, the Who had bigger things on their mind—or, at least, Townshend did. He grew almost instantaneously disillusioned with the youth-culture explosion emblemized by Woodstock; he saw that too many audience members were there to get wrecked on drugs and didn't particularly care about the music. His thirst for spiritual enlightenment had led him to guru Meher Baba, which had repercussions throughout his work (particularly Tommy), but his growing frustration, his inability to get the band to articulate his grand ideas, and the failure of their next big work, the aborted Lifehouse, led to a simultaneous thirst for brandy.

Even as they gradually tumbled down from their peak, the Who were good enough to salvage some wonderful things along the way—in particular, 1971's Who's Next, an essentially perfect album of rock thunder and majesty. Through the vessel of Daltrey's voice, Townshend seeks a higher power ("Bargain") while admitting that he falls prey to violence and anger ("Behind Blue Eyes"); he laments the self-destructive tendencies of youth culture ("Baba O'Riley") before triumphantly killing any and all idols ("Won't Get Fooled Again"). No other British band that emerged from the 1960s made work that contained this kind of psychological depth. But even then, the impish influence of Moon subverted the Who's most serious tendencies, resulting in the literal piss marks on the album's front cover.

With Moon's drumming becoming increasingly compromised by his drinking, 1973's Quadrophenia was a step back to the band's established strengths, a nostalgic period piece that examined the mod scene of the previous decade. Within this confined, real-world narrative, Townshend was able to successfully revisit his previous subject matter of youth and frustration. His incorporation of synthesizers and backing tracks into the band's sound, however, almost killed their live power, and subsequent Who projects clearly indicated that Townshend, increasingly reliant on alcohol, had drawn his most inventive period to a close.

It was Moon who became the Who's first casualty, in 1978. Lambert followed suit in 1981, several years after he and Stamp had parted ways acrimoniously with the band. (For more on the two managers' remarkable story, watch the terrific 2014 documentary Lambert and Stamp.) The Who carried on much longer than they should have, first with replacement drummer Kenney Jones, then on subsequent, infrequent reunion tours. To say they didn't cheapen the excellent work they'd done before would be disingenuous.

This latest exhumation of the Who's rich if somewhat tarnished legacy is likely to be the last. Without Moon and Entwistle, it could be argued that the very backbone of the band is gone—no other bassist and drummer were as fundamental to a band's sound as those two. But I'd say that, right now, Townshend and Daltrey are enough. Maybe they shouldn't even call it the Who, but that's their prerogative. They know it's a nostalgia act, and they know what songs their fans—many of whom are as old as they are—want to hear. It's been an amazing journey for the Who, a bumpy, often tragic trip up and down through rock's stratosphere. And maybe I'm naïve, but I'm absolutely interested in witnessing its final chapter. When you're on the brink of 20, it's easy enough to say you hope you die before you get old. That half of the Who failed to follow their own foolhardy directive is something to be thankful for.