On May 15, 1970, The Grateful Dead settled into New York's Fillmore East for a long night of music, both acoustic and electric. Their game-changing album Workingman's Dead—which marked a shift from psychedelic exploration to succinct, rootsy songs and helped kickstart the country-rock movement—was a month from release, and most of its songs show up here. The format of an acoustic set followed by an electric set (for both the early and late shows) reflected the stylistic orientation of the new material. Not only do the unplugged sets include Workingman's tunes like the ominous, bluesy "New Speedway Boogie" and the serene, harmony-laden folk-rocker "Uncle John's Band"; there are also such intriguing (relative) obscurities as Vern Stovall's classic country tune "Long Black Limousine" and the Bill Monroe gospel-bluegrass chestnut "A Voice from on High." Of course, delivering on that duality was crucial to the Dead's identity. The band kick out the jams in epic fashion in the electric sets too, with a satisfyingly spacy "Dark Star" and the greasy, churning "Turn On Your Lovelight."