The surviving original members of the Grateful Dead may have officially put the band to bed this past summer with the 50th anniversary ‘Fare Thee Well’ gigs in Chicago, but it was Jerry Garcia's death 20 years ago that really ended their long, strange trip. This four-disc set is a decent epitaph, with one track from each of the 30 years they were in operation, all previously unreleased live recordings (except for the earliest, a rare studio take of ‘Caution (Do Not Stop on Tracks)’). This chronological format highlights the rapid evolution that saw the Dead grow from a fuzzed-out R&B combo to something much more exploratory. By 1967 they'd already pushed way beyond traditional song structure, as the blazing 15-minute jam on ‘Viola Lee Blues’ from ’67 shows; but it was the signature tune ‘Dark Star’, captured here in 1968, that signalled a growing willingness to cast out into uncharted territory, at the same time as Garcia's lead guitar was leapfrogging the blues and even psychedelia and arriving at a much more high-risk, jazz-informed identity. The first two discs, bringing the story up to 1980, contain enough moments of spontaneous genius – Bob Weir sliding the two- chord “Tighten Up’ riff into ‘Dancing In The Streets’; the rolling group joy of ‘Franklin's Tower’; the slinky crawl of ‘Scarlet Begonias’ – to more than make up for the glossier and safer songs of the later years. When the Dead were in the zone, they flew like no one else.