were one of the very best R&B acts to come out of the U.K. during the British Invasion era, as tight, wiry, and potent as their contemporaries , , and . But as good as they were, their greatest strength was always their lead singer and main songwriter, , who even in his earliest days boasted a style that was raw and unapologetic but full of street smarts and imagination. 's run with lasted a bit more than two and a half years, but it laid the groundwork for his wildly idiosyncratic solo career as well as setting a standard that the band would never equal after he left to strike out on his own. There have been plenty of collections devoted to 's tenure with , but is not only comprehensive but has 's seal of approval, as it was assembled by 's own team and features liner notes from the man himself. Sequenced chronologically, devotes its first two discs to the group's two albums of the period, (aka ) and , as well as non-LP single and EP tracks. Disc two is devoted to demos, alternate takes, and some live tracks cut for BBC Radio, nearly all of them previously unreleased. According to 's notes, 's lineup was never consistent, especially in the studio, as the group's producers often brought in studio musicians (including ) to beef up the performances, but the product was both consistent and strong, with razor-sharp guitars and swirling organs dominating the arrangements and 's vocals sounding nearly possessed. Having essentially all of 's studio recordings in one place is great, but the bonus material offers a glimpse of their power as a live act, and the outtakes and alternate versions reveal the growing sophistication of 's approach over the course of 24 tracks. 's essay offers as much opinion as it does fact, but given his well-documented reticence, the fact he wrote the notes at all is impressive, and when he sums up his notes with "I think of as good records...there's a lot of good stuff here," he's absolutely right. As a history of an underappreciated band's greatest era or the first steps of one of rock's most individual artists, is essential listening. ~ Mark Deming