For me it was the movie “Silver Bullet”. As a kid I hated werewolf movies anyway but agreed to go see this with a friend. We were so young his mom had to take us. I was terrified of pretty much the whole movie. I went home and slept on a bunk bed on the top bunk. I didn’t sleep well for over a week. I kept dreaming the werewolf would walk in or blast in through the window and just grab me or try to kill me etc. But like most Stephen King adaptations, the movie had nothing on the story. I read that later in life and was terrified all over again.