On August 16 1938 in Greenwood Mississippi Robert Johnson one of the greatest bluesman of all time died in near anonymity at 27 He had appeared on the local musical scene a few years earlier but was rediscovered and made popular by a generation of rock stars of the 60s and 70s In 2014 two French cartoonists told Johnsons story in their graphic novel Love in Vain This documentary recounts their trip to Johnsons home state including interviews with a number of genuine bluesmen of the Deep South RL Boyce Watermelon Slim Ben Payton and Lucious Spiller among them