The prologue, titled He Said, She Said will be set in a dusty old museum, and will see the Doctor and Clara reflecting directly to camera how little they truly know about each other (the finale promises to reveal the 'secrets' of both the Doctor and Clara).
The prologue will be three minutes long and will be released online at 7.45pm on Saturday 11th May, straight after the broadcast of Nightmare in Silver. It will also be able to view on the red button in the UK between 7.40pm and midnight BST, and during the evening until the episode's broadcast the following Saturday.
The Name of the Doctor will be broadcast on Saturday 18th May.
[Source: Radio Times]