Very nice to have story that’s more character focused than plot focused, particularly when said character isn’t the Doctor. There didn’t seem to be a main character here, it was a true ensemble cast, with people from all walks of life.

It adds some interesting stuff to the vampire lore of the Whoniverse, and handles the ethical dilemma of using a clone race as fodder to further a specific cause in a far more interesting way than something like “New Earth”.