Forgive me for not having read any of the previous posts before chiming in on this (what I am about to say may have already been covered ad nosium)... I think I figured out a major part of the plotline for this game and, if I am correct, it makes a tremendous amount of sense for why it is in the Baldur's Gate franchise. I believe that Jergal is searching for a new mortal to take over the position occupied by Bhaal and we're the chosen candidates that are unknowingly interviewing for the spot. I also believe that Bhaal has other plans... and we're the unwitting pawns in a chess game between the two Gods.
Of course, I could be completely off my rocker... It's been known to happen from time to time... but that's my basic theory.
That's not a bad theory. I would throw in Shar too, since she seems to play a big role in the whole story.
