The Howling → Four knocks
I think its the 11th Doctor knocking. Both DT and RTD said it is not the master or anything you would think of, it is an emotional twist. 11 is life and death and he knocks on the door and forces the regeneration. Either that or RTD jumps the shark and its the Human Doctor and he kills 10. other than that its the valeyard played be Matt Smith Geffe71 17:51, December 31, 2009 (UTC)