How I met with Agatha Christie's Books?

I think, I was attending the second year of high school. A friend of mine, who was sitting next to me, was reading a novel. I just asked:
- What is its name?
He replied:
-"Ten Little Niggers" coldly. I thought he was impressed by the book.
-"Who is the author?" I asked.
- Agatha Christie.
-Yeah, this man, I said unknowingly.
He said :
-She is not male, but female .
At the same time, he showed me the back side of book. I just scared when I saw Christie's old and horrible face.

Then, my friend asked me for finding the murderer in the book. I guessed from the information that are given at the very early pages. Yet I was wrong.

Then, my curiosity about the killer drove me reading Ten Little Nigger. Obviously, as a masterpiece of Agatha, the book has made a very great effect on me, it was the nicest detective book, I ever read. And now Agatha became my favourite author.