Crito’s attempt to save Socrates has failed, so now we’ll go back and begin working through Plato’s dialogues from earlier in his life. First up are some discussions with various sophists, beginning with Protagoras.
This dialogue begins with a somewhat odd framing device; a friend meets Socrates walking through the city, and learns that he’s just come from speaking with Protagoras, who has recently arrived in Athens to work as a teacher. So, the rest of the work is Socrates recounting the meeting, so there’s a double narration going on, and the frame is never closed. I’m sure there’s been discussion enough of why the dialogue is structured this way, but I could only guess.