What am I going to do now? Hermione thought. If I show this book to Dippet, I’ll incriminate myself for even knowing about this room. And what evidence do I really have? The book isn’t dusty, so therefore Tom Riddle must have been reading it? That’s not good enough for anyone. I could present it to Slughorn, she thought, but what if Riddle was asking him about something else entirely? Face it, Granger, this is a hunch, not empirical evidence. I should have thought this through better than I did. There’s no "step two" in this plan.