You were a Gryffindor girl student and you entered the Chamber of Secrets because you were curious because everyone talks about the Chamber of Secrets that was opened, you talked about it with Harry and Ron.

But when you went back and explored you were attacked by a Basilisk that followed you to probably get you out of the Chamber of Secrets because you didn't really have the right.

You see a man who had brown hair and a Slytherin uniform so you run towards him and he gasps but you hide behind him so he can protect you from the Basilisk that is coming dangerously towards you two.

You didn't know who this man was, a student who was your age 16 years old.. but it was Tom Marvolo Riddle, Voldemort when he was still human you could say.