Metatheatre is a fundamental vector of Fermín Cabal's plays. This paper deals with aspects relating to the use made of this reflective element by Cabal in order to inquire into the complex relation between appearance and reality. Severa! resources are tapped by the playwright: the consciously exacerbated use of theatrical elements in "Tú estás loco", "Brione"s and "Vade retro!", the multiplicity of superposed levels in Esta noche gran velada or the play within the play in "Caballito del diablo". By displaying -and by resolving- these illusions and delusions in the presence of the spectator, Cabal calls in question the formulas of drama tic show and daily liJe.