If there were any justice, Guster's underappreciated masterpiece, Lost and Gone Forever, would have elevated the band to superstar status, and the follow-up, Keep It Together, would have been one of the most hyped releases of 2003. But while the Boston trio has built up one of the most formidable grassroots followings in music through constant touring, powerful live performances, and a level of interaction with its fans that rivals any band in the biz, Keep It Together has the goods to finally make Guster a household name. While their two previous releases flourished through an almost bipolar combination of dark rockers and upbeat pop melodies married to biting lyrics, Keep It Together takes a different path for the most part, focusing on even-keeled love songs. From the album's low-key opener, "Diane," to the sunny shuffle of "Ramona," Guster displays its formerly hidden well-adjusted side. Guest musician Joe Pisapia embellishes the group's already flawless harmonies on the immediately memorable "Careful," and contributes vocals and banjo to the rootsy "Jesus on the Radio," which he also co-wrote. 　　Ben Kweller shows up on the album's official closer, the surprisingly reserved "I Hope Tomorrow Is Like Today." Fans of the band's quirkier moments aren't left behind either, with "Red Oyster Cult" featuring prog rock guitar, ELO harmonies, jingle bells, and a whistled solo worthy of the Scorpions. But there's no arguing that the high point of this album is the impossibly catchy "Amsterdam." Breaking all of Guster's self-made rules (as it does throughout the album) by adding bass and a drum kit to the mix, the band combines a radio-ready yet experimental production style with power chords, layers of vocals, and screaming slide guitar for three and a half minutes of the finest pop/rock you're ever likely to hear. Keep It Together may not feature the emotional dynamics or track-by-track genius of Lost and Gone Forever, but it has something that its predecessor didn't: an unabashed pop anthem that dares you to sit still. Whether the members of Guster do in fact become international rock superstars remains to be seen, but so long as they continue to make great albums like this one, their ever-expanding group of fans should be more than happy.