Who Is the Timeless Child?

Bad Wolf. Torchwood. Harold Saxon. “There is something on your back.” “The Pandorica will open.” “Silence will fall.” “Run, you clever boy, and remember.” The Promised Land. The Hybrid. The Vault.

The first ten series of Doctor Who each had a mystery to solve, summed up by a particular phrase or name. And now, in keeping with the tradition, we've got a new one. The Timeless Child.

Except that the tradition was sort of broken, because Series 11 just mentioned the Timeless Child without...