If you turn the quest in at Hudson Barnes, the following conversation takes place:
Hudson Barnes says: I know this will seem like betrayal, but Mr. Hastings has made an offer I simply cannot refuse. My apologies, <Player>.
Hastings enters the inn.
Anson Hastings says: It's good to see you again, Mr. Barnes. Do you have the crate?
Hudson Barnes says: I do. <Player> just returned with it, but how do I know you're going to keep your end of the bargain?
Anson Hastings says: I have the charm with me and I will unlock its power once the crate is in my hands. You were wise to change your mind, Barnes.
Anson Hastings says: With it, you will be able to enter Karazhan without fear of harm or detection. Not even Harrison Jones will know how you uncover the tower's history.
Hudson Barnes says: Please, take the crate. I'm already thinking about what I'll find in the tower's library!
Anson Hastings says: I've been waiting for this day for years. Behold my transformation!
Hastings transforms into a spider.
Hudson Barnes says: No, wait! You haven't told me how to use this charm yet!
Anson Hastings says: What's happening to me? It burns!
Hastings dies.