I loved the confrontation between Barnabas and David in the mausoleum, and the fact that Barnabas mentioned their last confrontation there. Their positions were switched from the last time - previously Barnabas was the bad guy and David was the good guy, whereas today Barnabas was the good guy and David was being controlled by the bad guy - but their behavior was the same as before.
Why did Chris give Sabrina the key to his apartment? It really makes me wonder about him. He claims to be so horror-stricken at what he has done - but until Barnabas came along, he wasn't making much of an effort to stop it from happening. It seems as though something very strange is going on in his subconscious. Maybe the wolf persona doesn't entirely disappear from Chris when the moon sets. I don't think we're supposed to think that. I think we're supposed to think of Chris as a blameless innocent - but it just doesn't hold water.
The red light on Quentin's face was great. It didn't make any sense in terms of reality, but who cares? Blood red was the right color for him.