Even the Beach Boys' sunniest songs include a bittersweet tinge of melancholy, but by the early '70s, the band seemed surrounded by an inescapable gloom.

The group's 17th album, Surf's Up, caught them at a particularly vulnerable moment. Just five years removed from the creative breakthrough of Pet Sounds, they'd been hit hard by problems both internal — chief songwriter Brian Wilson spent years sidelined by a variety of mental and emotional issues — and external, as changing trends and new rock subgenres left their once-thrilling vocal blend sounding dated.

It all added up to a precipitous sales slump for the once-dominant band, which in turn fed into a period of creative drift that found the lineup splitting into factions and churning in flux. Without Wilson to rally behind, the Beach Boys strained to achieve internal equilibrium even as they fought the growing perception that they were over the hill. Hopes were high when they departed longtime label home Capitol in order to establish their own imprint, the Reprise-distributed Brother Records, but their first release through the new arrangement, 1970's Sunflower, was their lowest-charting collection of new material to date.

Yet even at their most scattered, the Beach Boys remained capable of startling beauty, and Surf's Up is a case in point. Released Aug. 30, 1971, it presented a snapshot of a disorganized group whose members occasionally seemed to be running on creative fumes — and yet as uneven as the record is, it's punctuated with bursts of spine-tingling harmony and heartbreaking insight that are almost enough to outweigh its ham-handed moments. It never quite coheres, but it's also never less than interesting, and bits and pieces shine as brightly as anything in the group's incredible catalog.

Like much of what the band released during this period, the parts of Surf's Up that work do so essentially in spite of everything that was happening behind the scenes. The record's genesis came from Brian Wilson, who'd turned his energies to running a health food store he'd named the Radiant Radish, making the acquaintance of journalist Jack Rieley, a passionate Beach Boys fan who used their interview as the opening for a personal relationship that led to Rieley ultimately taking over as the band's manager.

It would later be revealed that Rieley had fudged his qualifications to some extent, but he was a passionate fan with a collector's knowledge of the group's increasingly legendary unreleased material and a few unorthodox ideas about how to make the Beach Boys hip again. Both sides of this approach came into play with Surf's Up: The title track, which closes the album, had originally been recorded for the long-shelved Smile project, and made the track listing after Rieley convinced Wilson it needed to see release. While looking back, he tried to push the band ahead by urging them to write more topical lyrics focusing on the issues of the day.

Rieley's push for Beach Boys songs inspired by current events produced mixed results. The album opens with "Don't Go Near the Water," an anti-pollution anthem that adds an ecologically aware undercurrent to the group's longstanding depiction of the ocean as a place for fun in the sun. Less successful is "Student Demonstration Time," a fairly clumsy attempt to comment on civic unrest with new lyrics set to Lieber and Stoller's "Riot in Cell Block Number 9." Neither track is as flat-out weird as "A Day in the Life of a Tree," with lyrics (and lead vocals) by Rieley presenting a first-person account of ... a day in the life of a tree.

Patient fans who sifted through the record's less inspired moments, however, were rewarded with a handful of low-key Beach Boys gems. Carl Wilson, whose role in the band had been chiefly a vocalist and guitarist to that point, contributed the Rieley co-writes "Long Promised Road" and "Feel Flows," both of which stood among Surf's Up's highlights — the former ultimately becoming one of the band's better songs throughout its post-Pet Sounds period — while presaging the greater creative role he'd assume in the years to come.

In terms of new music from Brian Wilson, meanwhile, fans were forced to make do with "A Day in the Life of a Tree," but Surf's Up pulled some worthy notes from his back pages. The haunting title track, which Wilson had to be cajoled into finishing, satisfied years of pent-up demand, while its predecessor, "'Til I Die," distilled the Beach Boys' ability to wring beauty out of existential sorrow. Taken together, they were just enough to balance out the inclusion of "Take a Load Off Your Feet," a deeply inessential older number about foot care.

It wasn't the Beach Boys' most consistent effort, but unlike Sunflower, Surf's Up arrived at the right moment to find a receptive audience. The album peaked at No. 29, the band's highest showing in years, and hinted at brighter days to come from a group already stuck between its storied past and an uncertain future. This comeback proved fleeting, but there'd be others after it — and more painful setbacks between.

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