Most good stories start with a fundamental list of ingredients: the initial situation, conflict, complication, climax, suspense, denouement, and conclusion. Great writers sometimes shake up the recipe and add some spice.
Initial Situation
Aeneas and the Trojan fleet arrive in Libya.
The beginning of the story reveals the Trojans have already set out on their mission: to found a new home in Italy.
Conflict
Dido and Aeneas have a torrid, steamy, passionate love affair.
Due to its torridness and passion, Aeneas's fling with Dido runs the risk of distracting him from his main task.
Complication
Aeneas learns that he has to go down to the underworld before he can continue on to Latium.
This means yet another obstacle that will need to be met before Aeneas can go snap digital photos of the future site of the Roman forum (currently filled with cows).
Climax
Aeneas goes to the underworld and meets Anchises, who shows him the highlight reel of future Roman history.
It turns out that all Aeneas needed to do in the underworld was receive a motivational pep-talk. Now he's all good to go for some butt-kicking in Italy.
Suspense
Aeneas and the Trojans fight a war with the Turnus and the Italians.
This is the moment when Aeneas's plan seems most in danger of not being carried out – or at least being really, really messy.
Denouement
Aeneas defeats the Turnus and kills him.
By killing Turnus, Aeneas decisively removes the last obstacle standing between himself and his new life with Lavinia as king of the Latins and Trojans.
Conclusion
There is no conclusion.
One of the most striking features of the Aeneid is that it ends simply with Turnus's soul heading down to the underworld in anger. We never get to see how things play out – whether Aeneas and Lavinia are happy together, etc. In fact, this lack of a tidy ending so annoyed readers in the Renaissance that a few Italian writers tried to write their own conclusions to the poem.