Darkling

At first I thought it was about Kes, and in some respects it is. But the real focus is the Doctor, who is continually morphing from hologram to a real boy (like Pinocchio). In the process of bringing about some of the most creative beings in history and incorporating them into his design, he also takes on their weaknesses and dark sides. Once the good stuff is removed, a mass of blackness turns our balding fellow into a horror show. Oh, and he leads Kes around. And why did she make the decision she did at the conclusion?