G.K. Chesterton's book on Robert Louis Stevenson is a thorough critical exploration of Stevenson's work and philosophy, not simply a chronological biography. Chesterton aimed to restore focus to Stevenson's literary merit and counteract the trend of his time focusing too much on the anecdotal and romantic aspects of Stevenson's personal life. Chesterton highlights Stevenson's distinctive writing style, which he describes as having sharp outlines and vibrant colors. The book also serves as a defense against critics who downplayed Stevenson's work after his death, emphasizing the importance of his enduring literary legacy.