Robert Louis Stevenson (1850–1894) created two particularly memorable fictional doctors: David Livesey in Treasure Island (1883) and Henry Jekyll in Strange Case of Dr Jekyll and Mr Hyde (1886). This article offers a reading of these physicians as literary enactments of their real-life counterparts, whose demonstrations of narrative competence, or lack thereof, have far-reaching implications for both their patients and themselves. It explorers Hyde and Livesey's shortcomings and successes in relation to their respective engagement with principles of medical humanities. Comparing the two characters is especially appropriate since their narratives can be contextualised in the Scottish literary tradition within which Stevenson so consciously wrote. Variations on the doppelgänger motif (doubles, duality, multiple perspectives) are of course intrinsic to Scotland's cultural history – and Stevenson's almost obsessive interaction with this tradition finds embodiment in characters and situations throughout his oeuvre. Thus, it is intriguing to engage in an intertextual reading of the author's most famous clinicians as doppelgängers: Livesey, whose decisions are ultimately life-giving for himself, his colleagues, and his patients, and Jekyll, whose choices eventually lead to tragedy, comprise an ideal fictional case study for exploring Stevenson's portrayal of narrative competence as it pertains to medical practice.