The tragic downfall of Syd Barrett following the former Pink Floyd guitarist's descent into drug-induced madness haunts the band’s 1975 album Wish You Were Here. Written by Roger Waters and David Gilmour, the title track is an ode to their fallen comrade. Eerily, Barrett showed up out of the blue at Abbey Road Studios during the recording of this song in such rough shape that no one recognized him at first. “He stood up and said, ‘Right, when do I put my guitar on?’” keyboardist Rick Wright told Rolling Stone. “And we said, ‘Sorry, Syd, the guitar’s all done.’”