This dissertation takes Plutarch's paired biographies of Theseus and Romulus as a path to understanding a number of roles that the author assumes: as a biographer, an antiquarian, a Greek author under Roman rule. As the preface to the Theseus-Romulus makes clear, Plutarch himself sees these mythological figures as qualitatively different from his other biographical subjects, with the consequence that this particular pair of Lives serves as a limit case by which it is possible to elucidate the boundaries of Plutarch's authorial identity. They present, moreover, a set of opportunities for him to demonstrate his ability to curate and present familiar material (the founding of Rome, Theseus in the labyrinth) in demonstration of his broad learning. To this end, I regard the Theseus-Romulus as a fundamentally integral text, both of whose parts should be read alongside one another and the rest of Plutarch's corpus rather than as mere outgrowths of the traditions about the early history of Athens and Rome, respectively. Accordingly, I proceed in each of my four chapters to attend closely to a particular thematic cluster that appears in both Lives, thereby bringing to light the complex figural play by which Plutarch enlivens familiar material and demonstrates his virtuosity as author.In chapter 1, I take the preface to the Lives as my starting point, placing particular emphasis on the cartographic metaphor by which Plutarch figures the writing of biography about these mythological figures as a journey outward into unknown territories. In accounting for the surprising and counterintuitive aspects of this metaphor, I argue that Plutarch is engaging with competing models of the world, correlated with generic distinctions, and resolving them by the rhetorical strategy of syneciosis, the alignment of opposites. He is, moreover, inviting the reader to attend closely to the spatiotemporal dynamics of the Theseus and Romulus narratives, which one can understand as a set of movements along various axes and which unfold both alongside and against the metanarrative journey upon which Plutarch imagines himself as embarking in the preface to these Lives.In chapter 2, I build upon this spatial framework in order to explore the role of opsis (sight, vision) in Plutarch's approach to history and biography. Proceeding from Plutarch's intention, as he expresses it in the preface, to make the mythological material "take on the look of history," I argue that opsis serves as a thematic preoccupation for Plutarch in the Theseus-Romulus, both on the level of his biographical project and within the narratives of these Lives. In surveying incidents of sight in both parts, I note that way in which opsis can grant discursive authority to the one who sees something happen (most paradigmatically, a messenger such as Proculus at the end of Romulus) but can also overwhelm or "captivate" viewers and deprive them of agency. Indeed, it is this twofold potential of opsis that informs Plutarch's nuanced model of how biography, myth, and history might "look." For chapter 3, I turn to mimetic and imitative ideas in the Theseus-Romulus and underscore how Plutarch employs the recursive and iterative capacities of mimēsis to build large networks that serve to connect reader, author, and both biographical subjects in various ways. Since it is a term that can take a wide range of people and objects as "input" and "output," it appears in a particularly diverse set of circumstances in these Lives, and with a range of ethical evaluations that do not always align with the idea of ethical exemplarity implicit in Plutarch's project in the Parallel Lives. At the same time, engagement with mimetic behavior is a key respect by which Plutarch differentiates his two biographical subjects in the Theseus-Romulus: the former is heavily bound up in imitation, especially in his relationship to Heracles and his institution of the crane dance on Delos, while Plutarch emphasizes the latter's special status as founder of the new city of Rome by describing him as fundamentally non-imitative. In the final chapter, I turn to the motif of lēthē (forgetting) in the Theseus-Romulus, taking as my starting point Theseus 22, where Theseus neglects to change the sail on his ship to indicate his survival and Aegeus kills himself in the mistaken belief that his son is dead. I contend that Plutarch's version of the story, which explains Theseus' lapse as the result of his joy, relies on the pseudo-etymological link between joy (chara) and (choros) that Plato lays out in Laws II (645a). Broadening my focus, I look to the rest of the Theseus-Romulus and argue that Plutarch constructs a model of lēthē as a necessary element in cultural survival rather than a solely negative or destructive process. To reinforce this model, I suggest the familiar Ship of Theseus paradox at Theseus 23 as well as the trough in which Romulus and Remus survive at Romulus 7-8 as emblems of preservation in the face of change. More broadly, I contend that the survival, in Plutarch's own day, of Greek identity in the face of Roman domination is bound up with the capacity of lēthē to accommodate cultural transformation without annihilation.