Science fiction is just so fantastic. All you have to do is reverse the polarity of the flow of something or other (in a monolithic crystal matrix of course) and BAM! They, (the baddies), are all toast or scrap metal or whatever it is they're made off - scrap anyway. Go Doctor!
I had severe doubts about Ms Tate as the Doctors sidekick. Seemed a strange idea to use someone who was so well known in another genre and (forgive me) someone so mature as well. I warmed to her though.
Davros is just a memory now - cheers, you old Greek Island you.