The plane on the cover lets you know it's involved somehow. Reading the First Impression at first I think is this guy a stalker? They come to find out he's an agent and notices unusual people, actions, mannerisms. So he is watching this pretty blonde being a touch aggressive to get her through security, then a janitorial staffer is watching her. On & on it goes, but it just gets more and more intense. I have to read the rest of the story!