Doctor Who "The Power of Three" Review: Time Travel and Other Drugs

This week's episode marked a return to form that I hadn't seen in a while—the unlikely enemy. I simply adore it when really random things are repurposed as mysterious menaces on Doctor Who, and I especially love it when those enemies are global. However, the "A" story was hardly the point of the episode.
We opened on the Ponds doing some of the...  
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