Originally Answered: The Fountainhead. Agree or disagree with the philosophy?
Yes, she does get into your head. Even people who hate her can't forget her. But then, that's why they disrepect her so much--their minds are stuck with her.
Why does she have this effect? Because she was extremely good at isolating the concepts of human thought and behavior. How did she do that? By understanding epistemology. She said Atlas Shrugged was the only novel ever written where epistemology was the basis for each character; not their OCD routines, or their penchant for jokes, or their love of animals, but they way they thought.
Read Anthem next, if you have not already. It contains beautiful metaphysics (in other words, it will make you feel good--about living.)
And if you can, read Introduction to Objectivist Epistemology, Second Edition. It will teach you how the mind begins to think from birth, and how we come to have ideas.
Glad to have you on board. There are several YA users like you and me. Look for them, and read their answers. One is Luke, one is Ellis Wyatt, Atlas Shrugged, John Galt, all on my profile page. There are many more of us. Just look for answers that explain in good words, not bad ideas, what Rand and Objectivism was about.
And use the resource list on my blog:
P.S. Watch the movie with Gary Cooper.