John Barclay’s Argenis (1621) was an immediate smash hit in France, not least because the hero Poliarchus is a Frenchman. Indeed, it is rumored that Argenis was Cardinal Richelieu’s favorite novel, particularly because of the political dimension of this alleged roman à clé. Numerous French translations appeared between 1622 and 1630, and Nicolas Coeffeteau’s abridged version (1624) made the novel even more accessible to French readers. Taking advantage of the novel’s success, Pierre Du Ryer (1606-1658), one of the most popular playwrights of his generation, wrote two adaptations of Barclay’s novel: Argenis et Poliarque, ou Théocrine, tragicomédie (1630), focusses on the first encounter between Argenis and Poliarchus, whilst L’Argenis du sieur Du Ryer, tragi-comédie, dernière journée (1631) attempts to recount the entire plot.This article explores, through the prism of Du Ryer’s two plays, the poetics of adaptation of the neo-Latin novel to French tragicomedy. It approaches this question from narratological and performance viewpoints, and reflects on the politics of transgenericity, defined broadly as both the inscription of a genre in another and the passage from one mode of representation to another. This dual operation is political, in the sense that such a generic transformation is never insignificant, objective, or unmotivated. In fact, Du Ryer’s choice to adapt Argenis complicates the politics of spectacle at this time, especially since the dramatist’s patrons were not allies of Cardinal Richelieu, who was implementing reason of state policies and building an absolutist state.