Not a horrible query letter, in my opinion. Better than most I’ve read here. Work in just a little more plot, namely, who gets kidnapped and who gets murdered, and I think you have it.
I will disagree with maia about where to put the title and word count. The last place it should be is in the first paragraph. All it does there is slow everything waaaaay down, stop the agent from getting hooked, and often draws a quick rejection. Novel title and word count are boring, and boring should always be reserved for the last paragraph. Get right to the action with your first sentence.