[For once he's actually asking out of genuine curiosity and also to make a point. If Adam wants an answer, he's going to make him work for it, at least. It's the fact that he's open to these questions and that he's self-aware enough to realize what's happening that allows Luke to continue talking.]

Little of column A, little of column B. It's less of a question of how many murderers we have on this ship. I can probably guess just by looking at some of these people. It's the third parties I'm interested in. Who they are, if they really exist, what they're being offered...stuff like that. We're getting motives each week. What if the third parties are getting motives that are even greater in order to ensure silence and also getting them to carry out their bidding? I want to know how we could even tell that sort of thing.