John Steed: Who are you?
Dr. David Keel: I'm very sorry, I can't tell you that. But I'm on the side of the angels, believe me.
John Steed: [prepairing to leave] Right, that will have to satisfy you for the moment.
Dr. David Keel: I'm afraid that it doesn't!
John Steed: It will have to, for the time being, Doctor Keel. I'm very sorry but you'll just have to trust me... or not.
Dr. David Keel: Thanks for the choice.
John Steed: Doctor Keel, do you know who killed your fiancée?
Dr. David Keel: No, I don't!
John Steed: I do. And if you don't trust me there isn't a cat in hell's chance of you finding out.