Plot in The Odyssey
The story begins in medias res (in the middle of things). Homer assumes the audience is familiar with the traditional story. He begins at a moment of crisis, gradually drawing in the background material and employing the “flashback” technique. Odysseus tells the earlier story of some of his adventures to folks he meets in a later part of his journey.
The plot is not linear, and there are subplots. The story of Telemachus (often called The Telemachia) is a subplot.