Script Analysis

Calling all film buffs!

I desperately require your assistance.

As part of a screenwriting module at uni (from September) I am required to analyse a script.  As far as I'm aware, it is a movie script and can be from any movie I wish.

My favourite film ever is Stand By Me but, as much as I love it, I don't think that would be the best screenplay to analyse.

What would you consider to be a clever, interesting and generally fantastic screenplay to analyse?

I appreciate any guidance you have to offer and am open to all ideas.  If you provide reasons as to why you think your chosen screenplay is worth analysing, that would certainly help also.

Thanks in advance!