Introduction -- Defining the platonic sophists -- The "great speech" in Plato's Protagoras -- Prodicus: diplomat, sophist and teacher of Socrates -- The sophist Hippias and the problem of Polytropia -- Brother sophists: Euthydemus and Dionysodorus -- Protagorean sophistry in Plato's Theaetetus -- Plato's Critique of the sophists? -- Appendix: a primer on Hesiod's Myth of Prometheus