Most likely one of Plato's later dialogues, and certainly one of his more famous, the Phaedrus is one of Plato's most direct addresses on the subject of rhetoric and, one would figure, the sophists that normally served as his foil. Running throughout, as in many of his works, is Plato's insistence that a comprehensive knowledge of a subject must first be obtained before creative thought within that realm can begin. Crucial to such an understanding is finding the pivot points, or "joints", which are of key importance to a things existence and interactions. It would seem that Plato would label the forms as those crucial points, though it is unclear how to find crucial points within the particulars of the world. We know that Plato distinguishes between that which is simple and that which is complex, though how this relates to change and particulars in the world is not directly addressed here.
This translation offers a lively and accessible reading of a dialogue that requires a bit of foreknowledge concerning Plato's other works. Rowe has provided copious notes concerning earlier references and potential vagaries in meaning. A good introduction to Plato's work and thoughts in general.