In Act One, we in the audience may be introduced to the Villain (think of Charnier in France preparing his heroin-smuggling operation or the Tripods being activated in their subterranean lairs by the super storm from space).
We may experience anticipatory chills at the Evil One’s apparition. But it’s not till Act Two that the Hero truly becomes engaged with the Bad Guy. That’s when you and I as writers have to pour oil on the fire.
I know, when I’m stuck in my Second Act, I remind myself, ‘Go back to the Villain. Make him or her smarter, make him/her more formidable, more ruthless, more dangerous.’