However much we may disagree about the meaning and function of the Iris-Lyssa scene in Euripides’ Heracles (815-73), we can be certain of one thing: it was meant to be startling. We can find, it is true, a handful of examples of the appearance of a deity in mid-action in tragedy, and no single feature of the scene to be discussed is without parallel, but viewed as a whole it is unique among the extant plays and the plays for which we have fragmentary evidence. For example, the appearance of Athena in Rhesus 595 ff. and the probable appearance of Artemis and Apollo during the course of Sophocles’ Niobe (cf. frs. 441a, 442, 445 Radt), must have been striking, but in each case the supernatural visitation advances the plot along not unexpected lines. In our scene the intervention of Iris and Lyssa drives the second part of the play in a completely surprising direction. Again, it is remarkable that two speaking characters appear and then not to agree but to quarrel heatedly about Lyssa’s assignment. The only even remote parallel is the discussion between Kratos and Hephaistos in Prometheus where the deities speak and act on ground-level and are found not at a crucial turning-point in the middle of the play, but at its beginning, when the disagreement of the speakers is a curtain-raiser to the more significant discord which pervades the drama.