works that employ "in medias res" often later use flashback and nonlinear narrative for exposition to fill in the backstory. in homer's "odyssey", we first learn about odysseus's journey when he is held captive on calypso's island. we then find out, in books ix through xii, that the greater part of odysseus's journey precedes that moment in the narrative. in homer's "iliad" there are fewer flashbacks, although it opens in the thick of the trojan war.