Fleetwood Mac were always an unlikely megagroup. In the '70s, their rivals for world domination -- the Eagles or Led Zeppelin or even Kiss -- each defined an entire genre and spawned legions of imitators. Fleetwood Mac, though, had an oddly singular sound and style, impossible to copy, even a little hard to describe: too prickly for pop, too lush for rock.
The group's definitive lineup resulted from a shotgun wedding between the remnants of a British blues band (Mick Fleetwood, John and Christine McVie) and an unknown California folk-rock duo (Lindsey Buckingham and Stevie Nicks). On paper, it didn't really make sense, but on stage the chemistry somehow proved magical. Off stage, it led to one of rock's greatest soap operas, with intertwining and collapsing love affairs documented on their 1977 masterpiece, ''Rumours.'' Those sparks, in turn, helped create songs so intoxicating and sturdy, they've been covered by artists ranging from Waylon Jennings to Smashing Pumpkins. Most recently, alt-jokesters Camper Van Beethoven have been performing 1979's sprawling epic ''Tusk'' in its entirety, while the Dixie Chicks have taken ''Landslide'' to the top of the charts.
Now, the definitive Mac roster is back for Say You Will, the band's first full studio album since 1987's forgettable ''Tango in the Night.'' Well, 80 percent of the roster is, anyway: Christine McVie has opted to sit this one out. And while the album's highlights shine brightly, the absence of the group's least heralded songwriter ultimately proves a significant obstacle.
Minus Christine, ''Say You Will'' is evenly split between the contributions of Buckingham and Nicks -- truly two of pop's great eccentrics, often best taken in limited doses. The Buckingham songs represent the latest steps in his chronicle of elegant paranoia. ''From the pneumatic drills and sharpened knives/Blood in the sky are you dead or alive,'' he spits in the antimedia rant ''Murrow Turning Over in His Grave.'' Nicks, of course, sticks to her ethereal, twirly witch persona, delivering lines like ''The smell of Nag Champa/Shadow of a stranger'' in that familiar raspy purr.
After the first few songs broadly address global concerns (summed up in the opener's title, ''What's the World Coming To''), ''Say You Will'' settles into the band's usual subject matter -- the perils of ill-fated love, betrayal, and suspicion. But where the group's real lives gave some heft and substance to these themes before, during, and after ''Rumours,'' now this territory too often feels vague and flimsy.
The lyrics, though, have never really been as important to Fleetwood Mac as the sculpted sound -- in fact, by the time of such later releases as 1982's ''Mirage,'' the songs were glossed so excessively high, they slid right out of your brain. In the best moments on ''Say You Will,'' the textures of infinitely stacked guitars and voices express more than the words ever could. It's hard to decipher exactly what ''Illume (9-11)'' has to do with the World Trade Center attacks, but the feeling of loss and drift is undeniable. Too many of Buckingham's songs, though, feel so meticulously constructed and tinkered with that they get lost in his own head; cuts like ''Red Rover'' and ''Come'' seem hermetically sealed.
And yet, when the parts come together (more often, surprisingly, on Nicks' contributions), ''Say You Will'' soars like the Mac of old. The ebullient title track and the propulsive ''Thrown Down'' illustrate what this band is capable of -- the rich, layered production serving the songs, not just showing off; the supple rhythm section that gave the band its name swinging powerfully; the voices joining for the irresistible hooks and lifting us higher and higher.
But who would have guessed just how important Christine McVie was to the Mac mix? Though overshadowed by her bandmates' star power, her songs (''Say You Love Me,'' ''Over My Head,'' the effortless ''Tusk'' gem ''Think About Me'') were the glue that held the best Fleetwood Mac records together. Christine's husky vocals and clear emotions linked the band back to its blues base and grounded the quirk-and-quirkier team of Buckingham and Nicks.
The larger problem with ''Say You Will,'' however, might be that it's Fleetwood Mac's first real album of the CD era -- which means, like so many discs, it's way too long simply because it can be. ''Rumours'' and 1975's breakthrough, ''Fleetwood Mac,'' each contained 11 songs, and no one complained that they were missing anything. The 18 tracks here actually add up to an even longer playing time than the double LP ''Tusk,'' which was widely derided for being too rambling and self-indulgent. Memo to the Mac: ''Don't Stop'' might have worked as a theme for Bill Clinton, but it's not the right policy when choosing an album's track listing.