“What happens next?” is a simple question.
Any story makes you ask it. It is a powerful hook. What is going to happen to that guy who just lost his temper in front of his colleagues at work. What is going to happen to the girl whose mother just died?
“What happens next?” Well, keep on with the story and you'll find out.
“What happens next?” is the gateway drug of questions because now we are warmed up and ready to start asking deeper questions like, "how do I find happiness?" or "what does it mean to love someone?". If you hang with the story those questions will get answered too.