A lovely timey-wimey story from Moffat, which uses such a likeable main character to support, framed in such a wonderfully clever and unique way. The short form story also works as such an accessible format, which could easily hook children in, and to feel involved and seen in a Doctor Who story. So endearing, and works so well to bring children into this universe, by giving such a well rounded and likeable character they can see themself in.

While it doesn't have the advantages of Blink with the longer medium to build on this more, this is still a beautiful little story.