Introduce a Fascinating Protagonist (Protag):

These characters—hero, villain, victim—represent three opposing drives within every human being—the will to triumph, the impulse to destroy, and the hope to survive.

All have very clear first and last acts – a call to action and a final judgement – but between them too, within the constraints of reality they’re derived from, the same structure as Shakespeare, as Terence and as Horace.