Leo Percepied, aspiring writer and self-styled free-wheeling bum, gravitates to the subterraneans, impoverished intellectuals who haunt the bars of San Francisco. One of them is Mardou Fox, part Negro, part Cherokee, beautiful and a little crazy, whose dark eyes full of suffering and sweetness find recognition in Leo. But, afraid of his growing involvement, Leo sets out to destroy their love through betrayal and drunkenness.