As reported on io9, the ninth season of nu-Who doesn’t debut until September 19th, but you might as well get started with this moody but maddening vague two-minute “prologue” to the upcoming episodes.
As you can see, the Doctor is on Karn, last featured in the memorable minisode “The Night of the Doctor,” where Paul McGann returned as the Eighth Doctor and regenerated into Chris Eccleston’s Ninth John Hurt’s War Doctor with help from the Sisters of Karn. But that’s about all we know. Who is the Doctor meeting (or not meeting)? Why does the Doctor hand over his “Last Will and Testament” (as explained here) to the Sister, and what is she supposed to do it? What’s all this talk about friends and enemies about? Where is Clara?
You can view the trailer below.