In the comments below, (or in an email to me)
Paste a youtube link showing music from film or TV. Tell us why you picked it, and describe your clip in musical terms.
I picked the opening sequence from the horror movie "Insidious."
It appears to use stringed instruments, mostly violins, and they are using the classic horror movie recipe of creepy dynamics and dissonance. (Remember, consonance is when notes blend well together, dissonance is when they do not.)
It sounds like the violin's pitches are descending quickly, starting with high notes and dropping the pitch in a wobbly, turbulent, unsettling way. When the text featuring the movie title pops up, there is an explosion of more dissonance and tension that gives me the creeps and makes me jump every time. This is a great example of using harsh sounds to make scary images even scarier.