It’s a prequel or prologue, depending on how you want to think about it. The latest clip from Doctor Who isn’t from the next episode. No, it’s a prequel video a la last Summer’s Life with the Ponds.
There’s the same fun references to the Doctor’s recent past in this as we’ve come to expect, and it turns out to be a highly fun little clip.
Enjoy it, as it’s just a week til the good Doctor makes his valiant return.