Dear Miss Snark:
After rewriting my 250-word hook for the 250th time (hyperbole, but only slight), I find myself going back and forth on whether or not to "giveaway" dramatic plot turns. Obviously, you would not do this in trying to hook a reader, but you might in trying to hook an agent. Your consideration is urgently requested (so I don't hit 500 rewrites.)
Hoisted on My Own Hook
I cannot advise you on what to do about this. I can only tell you what works and what doesn't when you actually send it. Generally the more suspense, the more enticing the better.
You might watch some movie previews and listen to the voice over, and see what scenes are played. Lots of DVDs now have previews embedded.
You've got lots of time. Seven whole days in fact. God created the world in less time than that!