I was about 13 (back in the 70s), and I was sleeping over at a friends house in New York City. All the other kids had gone to sleep, but I was sitting in a big leather chair in the family study. I saw the Basic D&D box on the shelf. I took it down and opened it. It blew my mind.
I stayed up all night, alone, just reading and trying to wrap my head around the concept. It was a thrill like no other I had experienced. When the others woke up, I put the materials back into the box and put the box back on the shelf. I didn't tell anyone about what I had read. I think I felt as if I had found a magical treasure that nobody else would understand. In fact, I didn't understand the whole of it.
Although I didn't play at that time, my D&D radar was switched on. A year later, another friend of mine mentioned that he played D&D, and on a school trip to Malaga, Spain, my friend taught me how to play during the 6 hour flight. We rolled dice on those little flip down tables and everything.
After that, I joined a game back home and that was the beginning of years of gaming.