This is a George Lowthar episode, so I was expecting the "Act III Twist."  As a result, the ending was not surprising.  I will say, though, that Mr. Lowthar, perhaps unintentionally, left me theologically uncomfortable.  She saved Mordred from death at Jack's hand, specifically to gain entrance into Drusilla's garden, leaving Jack to Mordred's torture.  This doesn't sound altruistic to me; this is very self-serving behavior.  Life and Death morality play.