This chapter demonstrates the range and uniqueness of the Roman playwrights’ uses of soliloquies in their dramatic texts, pointing to how they could serve, in incipient form, as paradigmatic models of the diverse ways of presenting solo actors on Renaissance stages. The comedies of Plautus and Terence and the tragedies of Seneca contain an abundance of single speaker scenes which manifest a great range of formal diversity: soliloquies in the purest sense of isolated self-address, soliloquies overheard (both unintentionally and intentionally) by eavesdroppers on stage, soliloquies spoken as prayers to the powers of heaven and hell, and soliloquies spoken through the fourth wall to the audience. Though highly artificial, the soliloquy could effectively achieve the playwright’s dramatic, rhetorical, and psychological purpose. The chapter situates innovative Roman uses of the soliloquy within the physical properties of its acting spaces and the Roman culture of imagines, death masks.