This thing has just been posted by BBC One – and we mean minutes ago at this writing.  Tranzalore is lighting up, and it’s not in a good way.  The Doctor is regenerating, cry the Daleks – but he’s already on his 12th (13th?) regeneration – how is this even possible?

Orbiting a quiet backwater planet, the massed forces of the universe’s deadliest species gather, drawn to a mysterious message that echoes out to the stars – and amongst them, the Doctor. Rescuing Clara from a family Christmas dinner, the Time Lord and his best friend must learn what this enigmatic signal means for his own fate and that of the universe.

This is going to be epic.

Time of the Doctor airs Christmas Day.