After I moderately enjoyed The Grief Collector, the Time Lord fairy tales are back to the same-old-same-old. You can guess how this story is going to go from page 1, and it does so without a single surprise. The second Doctor uses his recorder to lure away a group of Cybermats from a space station, and saves the day. Why bother riffing on "The Pied Piper of Hamlin" and use only the most basic part of its idea? Work with the creepiness of the concept, don't sanitize it!