Ugh. I can't imagine writing a hook, even though I'll have to.
It shouldn't be that hard. The whole process should be much simpler. The query letter should be, "Me author. You agent. Here book."
The agent should then reply (almost immediately!), "Me agent. Love book. You client."
Not long after, the following letter should show up: "Me editor. Big publisher. Book stupendous. Reaching waaaay down into company piggy bank."
Update: I just thought of the perfect hook! Short, snappy, catchy. Just generally terriffic.
The book opens with a building blowing up. So now my query letter will read:
Me author. You agent. Here book.
Man, that's a killer.