The two-part season finale kicks in with this dark episode. Up to that point, Zankou has mostly been decimating his own ranks, so while we know that he is powerful, he doesn't seem that threatening. Indeed, Zankou's master-plan does not involve brute force, but cunning and a very good knowledge of his enemies. Actually, his idea is brilliant, and not only from a villain's point of view. It seems coherent that, figuratively speaking, the sisters would be haunted by the memory of all the innocents they haven't been able to save over the years. So having their past failures physically come back to blame them really illustrates what the Charmed Ones must be feeling -no to mention having to vanquish the poor victims themselves. It shakes them enough for Zankou to get a hold of the Book of Shadows. However, I feel that those haunts could have been chosen better. Of all the lot, only Davidson is really familiar (though only if you remember season 3). Using other victims from past episodes would have been much more dramatic.
Meanwhile, Sheridan is back with a vengeance. Oddly enough, she still hasn't recovered her memories, and she never will, so that particular threat remains unfulfilled. But it doesn't make her less dangerous, and now she's willing to fight dirty by involving Darryl's wife in it -putting him in such a quandary that his only way out is to leave. Poor Darryl.
So this is a very dark episode, in the image of the rest of the season but without any humour to compensate for the morbid atmosphere. The scene where Phoebe wakes up with Tim's reanimated corpse beside her is quite scary, and as I said Zankou's plan is psychologically devastating, which partly justifies the sisters' decision next episode. On the other hand, the episode suffers from the same problem that plagues most first parts : a slow development with little action.
