When Samuel Beckett’s own production of Waiting for Godot—in German—toured to London’s Royal Court theater in 1976, Guardian critic Michael Billington noted that the actors playing Estragon and Vladimir were “physical and temperamental opposites.” Vladimir was huge and ungainly; Estragon was “short legged, crab-gaited … and moonfaced.” In Arin Arbus’s strong production of Beckett’s despairing modernist masterpiece, Paul Sparks and Michael Shannon aren’t so physically distinct, but their individual temperaments land where they need to.