Ok, I’m sure that this is going to be some conjecture, but there has always been something that has bugged me.

In the opening script crawl for Empire, it states that Vader is obsessed with finding young Skywalker. Why? What happened between episodes IV and V that suddenly Vader is obsessed with finding Luke? This has never really been explained. The only comment that Vader had about Luke in IV is ‘the Force is strong in this one.’ How does Vader even know who Luke is? Of course we can assume that Vader found out through the Force, but even that seems a little sketchy.

So if anyone has an explanation for this plot hole, I’m interested in hearing it. Also, I should state that I don’t read EU stuff and even when I have it has no bearing on the movies. For me, the movies are the only things that I feel are relevant. So, therefore the answer to this must be in the movies somewhere and I’m just not getting it. And you can’t use the Vader and Emperor scene either. Vader mentions the name Skywalker long before that.