In medias res

A narrative work beginning in medias res (Classical Latin: [ɪn mɛdiaːs reːs], lit. "into the middle things") opens in the midst of action (cf. ab ovo, ab initio). Often, exposition is bypassed and filled in gradually, either through dialogue, flashbacks or description of past events. For example, Hamlet begins after the death of Hamlet's father. Characters make reference to King Hamlet's death without the plot's first establishment of said fact. Since the play focuses on Hamlet and the revenge itself more so than the motivation, Shakespeare utilizes in medias res to bypass superfluous exposition.

Works that employ in medias res often, though not always, will subsequently use flashback and nonlinear narrative for exposition of earlier events in order to fill in the backstory. For example, 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. On the other hand, Homer's Iliad has relatively few flashbacks, although it opens in the thick of the Trojan War.

The Roman lyric poet and satirist Horace (65–8 BC) first used the terms ab ōvō ("from the egg") and in mediās rēs ("into the middle of things") in his Ars poetica ("Poetic Arts", c. 13 BC), wherein lines 147–149 describe the ideal epic poet:

Nor does he begin the Trojan War from the egg,

but always he hurries to the action, and snatches the listener into the middle of things. . . .

The "egg" reference is to the mythological origin of the Trojan War in the birth of Helen and Clytemnestra from the double egg laid by Leda following her seduction by Zeus in the guise of a swan.

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